Barrier type detection using time-of-flight and receive signal strength indication

ABSTRACT

Techniques are provided for utilizing wireless devices to detect and classify barriers between devices. An example method for detecting a change in state of a physical environment includes determining a first state of the physical environment based on one or more round trip time measurements and one or more received signal strength measurements associated with a first plurality of radio frequency signals exchanged with one or more wireless nodes; determining a second state of the physical environment based on one or more round trip time measurements and one or more received signal strength measurements associated with a second plurality of radio frequency signals exchanged with the one or more wireless nodes; and providing an indication of a state change in the physical environment based at least in part on a comparison of the first state and the second state.

BACKGROUND

A wireless local area network (WLAN) may be formed by one or more accesspoints (APs) that provide a shared wireless medium for use by a numberof client devices. Each AP, which may correspond to a Basic Service Set(BSS), periodically broadcasts beacon frames to enable compatible clientdevices within wireless range of the AP to establish and maintain acommunication link with the WLAN. WLANs that operate in accordance withthe IEEE 802.11 family of standards are commonly referred to as Wi-Finetworks, and client devices that communicate with the AP in a Wi-Finetwork may be referred to as wireless stations (STAs).

Some wireless devices may be configured to communicate with otherwireless devices using radio-frequency signals. For example, a networkmay include several Internet of Things (IoT) objects and devicesconfigured to wirelessly communicate with each other. Many IoT devicessuch as smart appliances, smart televisions, and smart thermostats maybe configured support wireless protocols such as Wi-Fi, Bluetooth and/orUltrawideband (UWB). The wireless channels between the wireless devices,and APs, may be used for radio frequency (RF) sensing applications. Thedevices may listen to and capture the channel parameters on thetransmissions between the devices. Variations in signal measurements maybe used to detect barriers between the devices. Improved barrierdetection techniques may be used in a variety of mapping and userapplications.

SUMMARY

An example method for detecting a change in state of a physicalenvironment according to the disclosure includes determining a firststate of the physical environment based on one or more round trip timemeasurements and one or more received signal strength measurementsassociated with a first plurality of radio frequency signals exchangedwith one or more wireless nodes; determining a second state of thephysical environment based on one or more round trip time measurementsand one or more received signal strength measurements associated with asecond plurality of radio frequency signals exchanged with the one ormore wireless nodes; and providing an indication of a state change inthe physical environment based at least in part on a comparison of thefirst state and the second state.

Implementations of such a method may include one or more of thefollowing features. Determining the first state may include determiningthat a barrier is present in the first state of the physical environmentbased on the one or more round trip time measurements and the one ormore received signal strength measurements associated with the firstplurality of radio frequency signals, and determining that a barrier isnot present in the second state of the physical environment may be basedon the one or more round trip time measurements and the one or morereceived signal strength measurements associated with the secondplurality of radio frequency signals. A barrier type associated with thebarrier may be determined. An indication of the barrier type may beprovided to one or more controllers. The barrier may be a liquid and theindication of the state change may be a flooding alarm. The physicalenvironment may include a door, and wherein determining the first stateincludes determining that the door is in an open state, and determiningthe second state includes determining that the door is in a closedstate. The physical environment may include a window, and whereindetermining the first state includes determining that the window is inan open state, and determining the second state includes determiningthat the window is in a closed state. The physical environment mayinclude a plurality of vehicles, wherein determining the first stateincludes determining that a first number of vehicles are present in thephysical environment, and determining the second state includesdetermining that a second number of vehicles are present in the physicalenvironment, and wherein the second number of vehicles is different fromthe first number of vehicles. The number of vehicles may include zerovehicles. The physical environment may include a plurality of itemsdisposed on one or more shelves, wherein determining the first stateincludes determining that a first number of items are disposed on theone or more shelves, and determining the second state includesdetermining that a second number of items are disposed on the one ormore shelves, and wherein the second number of items is different fromthe first number of items. The number of items may include zero items.The first plurality of radio frequency signals and the second pluralityof radio frequency signals may utilize at least one radio accesstechnology selected from a group consisting of WiFi, Bluetooth,ultrawideband (UWB), and fifth generation new radio. Radio frequencysensing information for the physical environment may be obtained, suchthat determining the first state of the physical environment ordetermining the second state of the physical environment are based atleast in part on the radio frequency sensing information. Angle ofarrival measurements based on the first plurality of radio frequencysignals or the second plurality of radio frequency signals may beobtained, such that determining the first state of the physicalenvironment or determining the second state of the physical environmentare based at least in part on the angle of arrival measurements. The oneor more wireless nodes may include a user equipment and/or an accesspoint.

Items and/or techniques described herein may provide one or more of thefollowing capabilities, as well as other capabilities not mentioned.Radio frequency (RF) signals exchanged between wireless nodes such asuser equipment, access points, and other wireless devices may beconfigured to detect barriers between the wireless nodes. Time-of-flighttechniques, such as round trip timing information, may be used todetermine a first range between the wireless nodes. Signal strengthmeasurements, such as received signal strength indicators, may be usedto determine a second range between the wireless nodes. Barriers betweenthe wireless nodes may cause attenuation of the RF signals and thusimpact the second range measurement. The level of attenuation may beused to determine the orientation and composition of the barriers. Thelocations and compositions of barriers may be used in mappingapplications. The presence of a barrier may be used to allow or denyelectronic transactions. The state of barriers, such as being open orclosed, may be detected by the RF signals. Barrier type information maybe used to determine a context for controllers associated with aphysical environment. Other capabilities may be provided and not everyimplementation according to the disclosure must provide any, let aloneall, of the capabilities discussed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified diagram of an example wireless communicationssystem.

FIG. 2 is a block diagram of components of an example user equipmentshown in FIG. 1 .

FIG. 3 is a block diagram of components of an exampletransmission/reception point shown in FIG. 1 .

FIG. 4 is a block diagram of components of an example server shown inFIG. 1 .

FIG. 5 is an example message flow for a round trip time measurementsession.

FIG. 6 is a diagram of an example proximity measurement.

FIG. 7 is a diagram of an example proximity measurement through abarrier.

FIG. 8 is a graphical example of a probability function for detecting abarrier with radio frequency signals.

FIG. 9 is a graph of example barrier scenarios.

FIGS. 10A and 10B are diagrams of an example vehicle locking andunlocking system utilizing barrier detection.

FIG. 10C is a process flow for an example method of granting access to avehicle based in part on barrier detection information.

FIG. 11 is a diagram of an example use case for generating indoor mapsbased in part on barrier detection information.

FIG. 12 is diagram of an example use case for improving network typologybased on barrier type information.

FIGS. 13A and 13B are diagrams of an example use case for utilizingbarriers to improve network throughput.

FIGS. 14A and 14B are diagrams of example use cases for device-to-devicedata sharing.

FIGS. 15A and 15B are diagrams of example use cases for utilizingbarrier detection in a home network.

FIGS. 16A and 16B are diagrams of example use cases for determining astate of a local environment based in part on barrier detectiontechniques.

FIG. 17 is an example framework diagram of a user equipment for barrierdetection.

FIG. 18 is a process flow for an example method of detecting a change ofstate for a physical environment.

FIG. 19 is a process flow for an example method of generating mappinginformation based on barrier detection.

FIG. 20 is a process flow for an example method of authorizing adevice-to-device data exchange based on barrier detection information.

FIG. 21 is a process flow for an example method for determining barriertype information.

DETAILED DESCRIPTION

Techniques are discussed herein for utilizing wireless devices fordetecting and classifying barriers between devices. Wireless nodes, suchas user equipment (UE), access points (APs), and other mobile devices,may use RF signaling to determine a range between the devices. Forexample, round trip time (RTT) signals may be used to generate a rangeestimate between two capable devices by measuring the time it takes foran RF signal to make a round trip between the two devices. The rangeestimated by such time-of-flight methods is typically more accurate thanrange estimates obtained via other RF techniques such as a receivedsignal strength indication (RSSI) because RSSI based range estimationsmay be significantly degraded due to fading, blockage and multipath. Acombination of RTT and RSSI measurements, however, may be used todetermine if the devices are separated by a barrier such as a concretewall or a glass window since some barriers will significantly affectRSSI while yielding little to no changes in observed RTT ranges betweendevices. The values of the RTT and RSSI signals may be used to classifydifferent types of barriers. Barrier type information may be applied toa variety of different use cases such as indoor mapping, proximitydetection, contact tracing, network optimization, home comfort andsecurity, and indoor navigation. These techniques and configurations areexamples, and other techniques and configurations may be used.

Referring to FIG. 1 , an example of a communication system 100 includesa UE 105, a Radio Access Network (RAN) 135, here a Fifth Generation (5G)Next Generation (NG) RAN (NG-RAN), and a 5G Core Network (5GC) 140. TheUE 105 may be, e.g., an IoT device, a location tracker device, acellular telephone, or other device. A 5G network may also be referredto as a New Radio (NR) network; NG-RAN 135 may be referred to as a 5GRAN or as an NR RAN; and 5GC 140 may be referred to as an NG Corenetwork (NGC). Standardization of an NG-RAN and 5GC is ongoing in the3^(rd) Generation Partnership Project (3GPP). Accordingly, the NG-RAN135 and the 5GC 140 may conform to current or future standards for 5Gsupport from 3GPP. The NG-RAN 135 may be another type of RAN, e.g., a 3GRAN, a 4G Long Term Evolution (LTE) RAN, etc. The communication system100 may utilize information from a constellation 185 of satellitevehicles (SVs) 190, 191, 192, 193 for a Satellite Positioning System(SPS) (e.g., a Global Navigation Satellite System (GNSS)) like theGlobal Positioning System (GPS), the Global Navigation Satellite System(GLONASS), Galileo, or Beidou or some other local or regional SPS suchas the Indian Regional Navigational Satellite System (IRNSS), theEuropean Geostationary Navigation Overlay Service (EGNOS), or the WideArea Augmentation System (WAAS). Additional components of thecommunication system 100 are described below. The communication system100 may include additional or alternative components.

As shown in FIG. 1 , the NG-RAN 135 includes NR nodeBs (gNBs) 110 a, 110b, and a next generation eNodeB (ng-eNB) 114, and the 5GC 140 includesan Access and Mobility Management Function (AMF) 115, a SessionManagement Function (SMF) 117, a Location Management Function (LMF) 120,and a Gateway Mobile Location Center (GMLC) 125. The gNBs 110 a, 110 band the ng-eNB 114 are communicatively coupled to each other, are eachconfigured to bi-directionally wirelessly communicate with the UE 105,and are each communicatively coupled to, and configured tobi-directionally communicate with, the AMF 115. The AMF 115, the SMF117, the LMF 120, and the GMLC 125 are communicatively coupled to eachother, and the GMLC is communicatively coupled to an external client130. The SMF 117 may serve as an initial contact point of a ServiceControl Function (SCF) (not shown) to create, control, and delete mediasessions.

FIG. 1 provides a generalized illustration of various components, any orall of which may be utilized as appropriate, and each of which may beduplicated or omitted as necessary. Specifically, although one UE 105 isillustrated, many UEs (e.g., hundreds, thousands, millions, etc.) may beutilized in the communication system 100. Similarly, the communicationsystem 100 may include a larger (or smaller) number of SVs (i.e., moreor fewer than the four SVs 190-193 shown), gNBs 110 a, 110 b, ng-eNBs114, AMFs 115, external clients 130, and/or other components. Theillustrated connections that connect the various components in thecommunication system 100 include data and signaling connections whichmay include additional (intermediary) components, direct or indirectphysical and/or wireless connections, and/or additional networks.Furthermore, components may be rearranged, combined, separated,substituted, and/or omitted, depending on desired functionality.

While FIG. 1 illustrates a 5G-based network, similar networkimplementations and configurations may be used for other communicationtechnologies, such as 3G, Long Term Evolution (LTE), etc.Implementations described herein (be they for 5G technology and/or forone or more other communication technologies and/or protocols) may beused to transmit (or broadcast) directional synchronization signals,receive and measure directional signals at UEs (e.g., the UE 105) and/orprovide location assistance to the UE 105 (via the GMLC 125 or otherlocation server) and/or compute a location for the UE 105 at alocation-capable device such as the UE 105, the gNB 110 a, 110 b, or theLMF 120 based on measurement quantities received at the UE 105 for suchdirectionally-transmitted signals. The gateway mobile location center(GMLC) 125, the location management function (LMF) 120, the access andmobility management function (AMF) 115, the SMF 117, the ng-eNB (eNodeB)114 and the gNBs (gNodeBs) 110 a, 110 b are examples and may, in variousembodiments, be replaced by or include various other location serverfunctionality and/or base station functionality respectively.

The UE 105 may comprise and/or may be referred to as a device, a mobiledevice, a wireless device, a mobile terminal, a terminal, a mobilestation (MS), a Secure User Plane Location (SUPL) Enabled Terminal(SET), or by some other name. Moreover, the UE 105 may correspond to acellphone, smartphone, laptop, tablet, PDA, tracking device, navigationdevice, Internet of Things (IoT) device, asset tracker, health monitors,security systems, smart city sensors, smart meters, wearable trackers,or some other portable or moveable device. Typically, though notnecessarily, the UE 105 may support wireless communication using one ormore Radio Access Technologies (RATs) such as Global System for Mobilecommunication (GSM), Code Division Multiple Access (CDMA), Wideband CDMA(WCDMA), LTE, High Rate Packet Data (HRPD), IEEE 802.11 WiFi (alsoreferred to as Wi-Fi), Bluetooth® (BT), Worldwide Interoperability forMicrowave Access (WiMAX), 5G new radio (NR) (e.g., using the NG-RAN 135and the 5GC 140), etc. The UE 105 may support wireless communicationusing a Wireless Local Area Network (WLAN) which may connect to othernetworks (e.g., the Internet) using a Digital Subscriber Line (DSL) orpacket cable, for example. The use of one or more of these RATs mayallow the UE 105 to communicate with the external client 130 (e.g., viaelements of the 5GC 140 not shown in FIG. 1 , or possibly via the GMLC125) and/or allow the external client 130 to receive locationinformation regarding the UE 105 (e.g., via the GMLC 125).

The UE 105 may include a single entity or may include multiple entitiessuch as in a personal area network where a user may employ audio, videoand/or data I/O (input/output) devices and/or body sensors and aseparate wireline or wireless modem. An estimate of a location of the UE105 may be referred to as a location, location estimate, location fix,fix, position, position estimate, or position fix, and may begeographic, thus providing location coordinates for the UE 105 (e.g.,latitude and longitude) which may or may not include an altitudecomponent (e.g., height above sea level, height above or depth belowground level, floor level, or basement level). Alternatively, a locationof the UE 105 may be expressed as a civic location (e.g., as a postaladdress or the designation of some point or small area in a buildingsuch as a particular room or floor). A location of the UE 105 may beexpressed as an area or volume (defined either geographically or incivic form) within which the UE 105 is expected to be located with someprobability or confidence level (e.g., 67%, 95%, etc.). A location ofthe UE 105 may be expressed as a relative location comprising, forexample, a distance and direction from a known location. The relativelocation may be expressed as relative coordinates (e.g., X, Y (and Z)coordinates) defined relative to some origin at a known location whichmay be defined, e.g., geographically, in civic terms, or by reference toa point, area, or volume, e.g., indicated on a map, floor plan, orbuilding plan. In the description contained herein, the use of the termlocation may comprise any of these variants unless indicated otherwise.When computing the location of a UE, it is common to solve for local x,y, and possibly z coordinates and then, if desired, convert the localcoordinates into absolute coordinates (e.g., for latitude, longitude,and altitude above or below mean sea level).

The UE 105 may be configured to communicate with other entities usingone or more of a variety of technologies. The UE 105 may be configuredto connect indirectly to one or more communication networks via one ormore device-to-device (D2D) peer-to-peer (P2P) links. The D2D P2P linksmay be supported with any appropriate D2D radio access technology (RAT),such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth®, 5G CV2XSidelink, 5G ProSe, and so on. One or more of a group of UEs utilizingD2D communications may be within a geographic coverage area of aTransmission/Reception Point (TRP) such as one or more of the gNBs 110a, 110 b, and/or the ng-eNB 114. Other UEs in such a group may beoutside such geographic coverage areas, or may be otherwise unable toreceive transmissions from a base station. Groups of UEs communicatingvia D2D communications may utilize a one-to-many (1:M) system in whicheach UE may transmit to other UEs in the group. A TRP may facilitatescheduling of resources for D2D communications. In other cases, D2Dcommunications may be carried out between UEs without the involvement ofa TRP.

Base stations (BSs) in the NG-RAN 135 shown in FIG. 1 include NR NodeBs, referred to as the gNBs 110 a and 110 b. Pairs of the gNBs 110 a,110 b in the NG-RAN 135 may be connected to one another via one or moreother gNBs. Access to the 5G network is provided to the UE 105 viawireless communication between the UE 105 and one or more of the gNBs110 a, 110 b, which may provide wireless communications access to the5GC 140 on behalf of the UE 105 using 5G. In FIG. 1 , the serving gNBfor the UE 105 is assumed to be the gNB 110 a, although another gNB(e.g. the gNB 110 b) may act as a serving gNB if the UE 105 moves toanother location or may act as a secondary gNB to provide additionalthroughput and bandwidth to the UE 105.

Base stations (BSs) in the NG-RAN 135 shown in FIG. 1 may include theng-eNB 114, also referred to as a next generation evolved Node B. Theng-eNB 114 may be connected to one or more of the gNBs 110 a. 110 b inthe NG-RAN 135, possibly via one or more other gNBs and/or one or moreother ng-eNBs. The ng-eNB 114 may provide LTE wireless access and/orevolved LTE (eLTE) wireless access to the UE 105. One or more of thegNBs 110 a, 110 b and/or the ng-eNB 114 may be configured to function aspositioning-only beacons which may transmit signals to assist withdetermining the position of the UE 105 but may not receive signals fromthe UE 105 or from other UEs.

The BSs (e.g., gNB 110 a, gNB 110 b, ng-eNB 114) may each comprise oneor more TRPs. For example, each sector within a cell of a BS maycomprise a TRP, although multiple TRPs may share one or more components(e.g., share a processor but have separate antennas). The system 100 mayinclude macro TRPs or the system 100 may have TRPs of different types,e.g., macro, pico, and/or femto TRPs, etc. A macro TRP may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by terminals with servicesubscription. A pico TRP may cover a relatively small geographic area(e.g., a pico cell) and may allow unrestricted access by terminals withservice subscription. A femto or home TRP may cover a relatively smallgeographic area (e.g., a femto cell) and may allow restricted access byterminals having association with the femto cell (e.g., terminals forusers in a home).

As noted, while FIG. 1 depicts nodes configured to communicate accordingto 5G communication protocols, nodes configured to communicate accordingto other communication protocols, such as, for example, an LTE protocolor IEEE 802.11x protocol, may be used. For example, in an Evolved PacketSystem (EPS) providing LTE wireless access to the UE 105, a RAN maycomprise an Evolved Universal Mobile Telecommunications System (UMTS)Terrestrial Radio Access Network (E-UTRAN) which may comprise basestations comprising evolved Node Bs (eNBs). A core network for EPS maycomprise an Evolved Packet Core (EPC). An EPS may comprise an E-UTRANplus EPC, where the E-UTRAN corresponds to the NG-RAN 135 and the EPCcorresponds to the 5GC 140 in FIG. 1 .

The gNBs 110 a. 110 b and the ng-eNB 114 may communicate with the AMF115, which, for positioning functionality, communicates with the LMF120. The AMF 115 may support mobility of the UE 105, including cellchange and handover and may participate in supporting a signalingconnection to the UE 105 and possibly data and voice bearers for the UE105. The LMF 120 may communicate directly with the UE 105, e.g., throughwireless communications. The LMF 120 may support positioning of the UE105 when the UE 105 accesses the NG-RAN 135 and may support positionprocedures/methods such as Assisted GNSS (A-GNSS), Observed TimeDifference of Arrival (OTDOA), Real lime Kinematics (RTK), Precise PointPositioning (PPP), Differential GNSS (DGNSS), Enhanced Cell ID (E-CID),angle of arrival (AOA), angle of departure (AOD), and/or other positionmethods. The LMF 120 may process location services requests for the UE105, e.g., received from the AMF 115 or from the GMLC 125. The LMF 120may be connected to the AMF 115 and/or to the GMLC 125. The LMF 120 maybe referred to by other names such as a Location Manager (LM), LocationFunction (LF), commercial LMF (CLMF), or value added LMF (VLMF). Anode/system that implements the LMF 120 may additionally oralternatively implement other types of location-support modules, such asan Enhanced Serving Mobile Location Center (E-SMLC) or a Secure UserPlane Location (SUPL) Location Platform (SLP). At least part of thepositioning functionality (including derivation of the location of theUE 105) may be performed at the UE 105 (e.g., using signal measurementsobtained by the UE 105 for signals transmitted by wireless nodes such asthe gNBs 110 a, 110 b and/or the ng-eNB 114, and/or assistance dataprovided to the UE 105, e.g. by the LMF 120).

The GMLC 125 may support a location request for the UE 105 received fromthe external client 130 and may forward such a location request to theAMF 115 for forwarding by the AMF 115 to the LMF 120 or may forward thelocation request directly to the LMF 120. A location response from theLMF 120 (e.g., containing a location estimate for the UE 105) may bereturned to the GMLC 125 either directly or via the AMF 115 and the GMLC125 may then return the location response (e.g., containing the locationestimate) to the external client 130. The GMLC 125 is shown connected toboth the AMF 115 and LMF 120, though one of these connections may besupported by the 5GC 140 in some implementations.

As further illustrated in FIG. 1 , the LMF 120 may communicate with thegNBs 110 a, 110 b and/or the ng-eNB 114 using a New Radio PositionProtocol A (which may be referred to as NPPa or NRPPa), which may bedefined in 3GPP Technical Specification (TS) 38.455. NRPPa may be thesame as, similar to, or an extension of the LTE Positioning Protocol A(LPPa) defined in 3GPP TS 36.455, with NRPPa messages being transferredbetween the gNB 110 a (or the gNB 110 b) and the LMF 120, and/or betweenthe ng-eNB 114 and the LMF 120, via the AMF 115. As further illustratedin FIG. 1 , the LMF 120 and the UE 105 may communicate using an LTEPositioning Protocol (LPP), which may be defined in 3GPP TS 36.355. TheLMF 120 and the UE 105 may also or instead communicate using a New RadioPositioning Protocol (which may be referred to as NPP or NRPP), whichmay be the same as, similar to, or an extension of LPP. Here, LPP and/orNPP messages may be transferred between the UE 105 and the LMF 120 viathe AMF 115 and the serving gNB 110 a, 110 b or the serving ng-eNB 114for the UE 105. For example, LPP and/or NPP messages may be transferredbetween the LMF 120 and the AMF 115 using a 5G Location ServicesApplication Protocol (LCS AP) and may be transferred between the AMF 115and the UE 105 using a 5G Non-Access Stratum (NAS) protocol. The LPPand/or NPP protocol may be used to support positioning of the UE 105using UE-assisted and/or UE-based position methods such as A-GNSS, RTK,OTDOA and/or E-CID. The NRPPa protocol may be used to supportpositioning of the UE 105 using network-based position methods such asE-CID (e.g., when used with measurements obtained by the gNB 110 a, 110b or the ng-eNB 114) and/or may be used by the LMF 120 to obtainlocation related information from the gNBs 110 a, 110 b and/or theng-eNB 114, such as parameters defining directional SS transmissionsfrom the gNBs 110 a, 110 b, and/or the ng-eNB 114.

With a UE-assisted position method, the UE 105 may obtain locationmeasurements and send the measurements to a location server (e.g., theLMF 120) for computation of a location estimate for the UE 105. Forexample, the location measurements may include one or more of a ReceivedSignal Strength Indication (RSSI), Round Trip signal propagation Time(RTT), Reference Signal Time Difference (RSTD), Reference SignalReceived Power (RSRP) and/or Reference Signal Received Quality (RSRQ)for the gNBs 110 a, 110 b, the ng-eNB 114, and/or a WLAN AP. Thelocation measurements may also or instead include measurements of GNSSpseudorange, code phase, and/or carrier phase for the SVs 190-193.

With a UE-based position method, the UE 105 may obtain locationmeasurements (e.g., which may be the same as or similar to locationmeasurements for a UE-assisted position method) and may compute alocation of the UE 105 (e.g., with the help of assistance data receivedfrom a location server such as the LMF 120 or broadcast by the gNBs 110a, 110 b, the ng-eNB 114, or other base stations or APs).

With a network-based position method, one or more base stations (e.g.,the gNBs 110 a, 110 b, and/or the ng-eNB 114) or APs may obtain locationmeasurements (e.g., measurements of RSSI, RTT, RSRP, RSRQ or Time OfArrival (TOA) for signals transmitted by the UE 105) and/or may receivemeasurements obtained by the UE 105. The one or more base stations orAPs may send the measurements to a location server (e.g., the LMF 120)for computation of a location estimate for the UE 105.

Information provided by the gNBs 110 a, 110 b, and/or the ng-eNB 114 tothe LMF 120 using NRPPa may include timing and configuration informationfor directional SS transmissions and location coordinates. The LMF 120may provide some or all of this information to the UE 105 as assistancedata in an LPP and/or NPP message via the NG-RAN 135 and the 5GC 140.

An LPP or NPP message sent from the LMF 120 to the UE 105 may instructthe UE 105 to do any of a variety of things depending on desiredfunctionality. For example, the LPP or NPP message could contain aninstruction for the UE 105 to obtain measurements for GNSS (or A-GNSS),WLAN, E-CID, and/or OTDOA (or some other position method). In the caseof E-CID, the LPP or NPP message may instruct the UE 105 to obtain oneor more measurement quantities (e.g., beam ID, beam width, mean angle,RSRP. RSRQ measurements) of directional signals transmitted withinparticular cells supported by one or more of the gNBs 110 a, 110 b,and/or the ng-eNB 114 (or supported by some other type of base stationsuch as an eNB or WiFi AP). The UE 105 may send the measurementquantities back to the LMF 120 in an LPP or NPP message (e.g., inside a5G NAS message) via the serving gNB 110 a (or the serving ng-eNB 114)and the AMF 115.

As noted, while the communication system 100 is described in relation to5G technology, the communication system 100 may be implemented tosupport other communication technologies, such as GSM, WCDMA, LTE, etc.,that are used for supporting and interacting with mobile devices such asthe UE 105 (e.g., to implement voice, data, positioning, and otherfunctionalities). In some such embodiments, the 5GC 140 may beconfigured to control different air interfaces. For example, the 5GC 140may be connected to a WLAN using a Non-3GPP InterWorking Function(N3IWF, not shown FIG. 1 ) in the 5GC 150. For example, the WLAN maysupport IEEE 802.11 WiFi access for the UE 105 and may comprise one ormore WiFi APs. Here, the N3IWF may connect to the WLAN and to otherelements in the 5GC 140 such as the AMF 115. In some embodiments, boththe NG-RAN 135 and the 5GC 140 may be replaced by one or more other RANsand one or more other core networks. For example, in an EPS, the NG-RAN135 may be replaced by an E-UTRAN containing eNBs and the 5GC 140 may bereplaced by an EPC containing a Mobility Management Entity (MME) inplace of the AMF 115, an E-SMLC in place of the LMF 120, and a GMLC thatmay be similar to the GMLC 125. In such an EPS, the E-SMLC may use LPPain place of NRPPa to send and receive location information to and fromthe eNBs in the E-UTRAN and may use LPP to support positioning of the UE105. In these other embodiments, positioning of the UE 105 usingdirectional PRSs may be supported in an analogous manner to thatdescribed herein for a 5G network with the difference that functions andprocedures described herein for the gNBs 110 a, 110 b, the ng-eNB 114,the AMF 115, and the LMF 120 may, in some cases, apply instead to othernetwork elements such eNBs, WiFi APs, an MME, and an E-SMLC.

As noted, in some embodiments, positioning functionality may beimplemented, at least in part, using the directional SS beams, sent bybase stations (such as the gNBs 110 a, 110 b, and/or the ng-eNB 114)that are within range of the UE whose position is to be determined(e.g., the UE 105 of FIG. 1 ). The UE may, in some instances, use thedirectional SS beams from a plurality of base stations (such as the gNBs110 a, 110 b, the ng-eNB 114, etc.) to compute the UE's position.

Referring also to FIG. 2 , a UE 200 is an example of the UE 105 andcomprises a computing platform including a processor 210, memory 211including software (SW) 212, one or more sensors 213, a transceiverinterface 214 for a transceiver 215 (that includes a wirelesstransceiver 240 and a wired transceiver 250), a user interface 216, aSatellite Positioning System (SPS) receiver 217, a camera 218, and aposition (motion) device 219. The processor 210, the memory 211, thesensor(s) 213, the transceiver interface 214, the user interface 216,the SPS receiver 217, the camera 218, and the position (motion) device219 may be communicatively coupled to each other by a bus 220 (which maybe configured, e.g., for optical and/or electrical communication). Oneor more of the shown apparatus (e.g., the camera 218, the position(motion) device 219, and/or one or more of the sensor(s) 213, etc.) maybe omitted from the UE 200. The processor 210 may include one or moreintelligent hardware devices, e.g., a central processing unit (CPU), amicrocontroller, an application specific integrated circuit (ASIC), etc.The processor 210 may comprise multiple processors including ageneral-purpose/application processor 230, a Digital Signal Processor(DSP) 231, a modem processor 232, a video processor 233, and/or a sensorprocessor 234. One or more of the processors 230-234 may comprisemultiple devices (e.g., multiple processors). For example, the sensorprocessor 234 may comprise. e.g., processors for radar, ultrasound,and/or lidar, etc. The modem processor 232 may support dual SIM/dualconnectivity (or even more SIMs). For example, a SIM (SubscriberIdentity Module or Subscriber Identification Module) may be used by anOriginal Equipment Manufacturer (OEM), and another SIM may be used by anend user of the UE 200 for connectivity. The memory 211 is anon-transitory storage medium that may include random access memory(RAM), flash memory, disc memory, and/or read-only memory (ROM), etc.The memory 211 stores the software 212 which may be processor-readable,processor-executable software code containing instructions that areconfigured to, when executed, cause the processor 210 to perform variousfunctions described herein. Alternatively, the software 212 may not bedirectly executable by the processor 210 but may be configured to causethe processor 210, e.g., when compiled and executed, to perform thefunctions. The description may refer to the processor 210 performing afunction, but this includes other implementations such as where theprocessor 210 executes software and/or firmware. The description mayrefer to the processor 210 performing a function as shorthand for one ormore of the processors 230-234 performing the function. The descriptionmay refer to the UE 200 performing a function as shorthand for one ormore appropriate components of the UE 200 performing the function. Theprocessor 210 may include a memory with stored instructions in additionto and/or instead of the memory 211. Functionality of the processor 210is discussed more fully below.

The configuration of the UE 200 shown in FIG. 2 is an example and notlimiting of the disclosure, including the claims, and otherconfigurations may be used. For example, an example configuration of theUE includes one or more of the processors 230-234 of the processor 210,the memory 211, and the wireless transceiver 240. Other exampleconfigurations include one or more of the processors 230-234 of theprocessor 210, the memory 211, the wireless transceiver 240, and one ormore of the sensor(s) 213, the user interface 216, the SPS receiver 217,the camera 218, the PMD 219, and/or the wired transceiver 250.

The UE 200 may comprise the modem processor 232 that may be capable ofperforming baseband processing of signals received and down-converted bythe transceiver 215 and/or the SPS receiver 217. The modem processor 232may perform baseband processing of signals to be upconverted fortransmission by the transceiver 215. Also or alternatively, basebandprocessing may be performed by the general-purpose processor 230 and/orthe DSP 231. Other configurations, however, may be used to performbaseband processing.

The UE 200 may include the sensor(s) 213 that may include, for example,an Inertial Measurement Unit (IMU) 270, one or more magnetometers 271,and/or one or more environment sensors 272. The IMU 270 may comprise oneor more inertial sensors, for example, one or more accelerometers 273(e.g., collectively responding to acceleration of the UE 200 in threedimensions) and/or one or more gyroscopes 274. The magnetometer(s) mayprovide measurements to determine orientation (e.g., relative tomagnetic north and/or true north) that may be used for any of a varietyof purposes, e.g., to support one or more compass applications. Theenvironment sensor(s) 272 may comprise, for example, one or moretemperature sensors, one or more barometric pressure sensors, one ormore ambient light sensors, one or more camera imagers, and/or one ormore microphones, etc. The sensor(s) 213 may generate analog and/ordigital signals indications of which may be stored in the memory 211 andprocessed by the DSP 231 and/or the general-purpose processor 230 insupport of one or more applications such as, for example, applicationsdirected to positioning and/or navigation operations. The sensorsprocessing subsystem may be embedded in a low power core thatfacilitates continuous logging and derivation of sensor parametersrequired for high level functions such as temperature sensing, locationassist or dead reckoning.

The sensor(s) 213 may be used in relative location measurements,relative location determination, motion determination, etc. Informationdetected by the sensor(s) 213 may be used for motion detection, relativedisplacement, dead reckoning, sensor-based location determination,and/or sensor-assisted location determination. The sensor(s) 213 may beuseful to determine whether the UE 200 is fixed (stationary) or mobileand/or whether to report certain useful information to the LMF 120regarding the mobility of the UE 200. For example, based on theinformation obtained/measured by the sensor(s) 213, the UE 200 maynotify/report to the LMF 120 that the UE 200 has detected movements orthat the UE 200 has moved, and report the relative displacement/distance(e.g., via dead reckoning, or sensor-based location determination, orsensor-assisted location determination enabled by the sensor(s) 213). Inanother example, for relative positioning information, the sensors/IMUcan be used to determine the angle and/or orientation of the otherdevice with respect to the UE 200, etc.

The IMU 270 may be configured to provide measurements about a directionof motion and/or a speed of motion of the UE 200, which may be used inrelative location determination. For example, the one or moreaccelerometers 273 and/or the one or more gyroscopes 274 of the IMU 270may detect, respectively, a linear acceleration and a speed of rotationof the UE 200. The linear acceleration and speed of rotationmeasurements of the UE 200 may be integrated over time to determine aninstantaneous direction of motion as well as a displacement of the UE200. The instantaneous direction of motion and the displacement may beintegrated to track a location of the UE 200. For example, a referencelocation of the UE 200 may be determined, e.g., using the SPS receiver217 (and/or by some other means) for a moment in time and measurementsfrom the accelerometer(s) 273 and gyroscope(s) 274 taken after thismoment in time may be used in dead reckoning to determine presentlocation of the UE 200 based on movement (direction and distance) of theUE 200 relative to the reference location.

The magnetometer(s) 271 may determine magnetic field strengths indifferent directions which may be used to determine orientation of theUE 200. For example, the orientation may be used to provide a digitalcompass for the UE 200. The magnetometer(s) 271 may include atwo-dimensional magnetometer configured to detect and provideindications of magnetic field strength in two orthogonal dimensions.Also or alternatively, the magnetometer(s) 271 may include athree-dimensional magnetometer configured to detect and provideindications of magnetic field strength in three orthogonal dimensions.The magnetometer(s) 271 may provide means for sensing a magnetic fieldand providing indications of the magnetic field, e.g., to the processor210.

The transceiver 215 may include a wireless transceiver 240 and a wiredtransceiver 250 configured to communicate with other devices throughwireless connections and wired connections, respectively. For example,the wireless transceiver 240 may include a transmitter 242 and receiver244 coupled to one or more antennas 246 for transmitting (e.g., on oneor more uplink channels and/or one or more sidelink channels) and/orreceiving (e.g., on one or more downlink channels and/or one or moresidelink channels) wireless signals 248 and transducing signals from thewireless signals 248 to wired (e.g., electrical and/or optical) signalsand from wired (e.g., electrical and/or optical) signals to the wirelesssignals 248. Thus, the transmitter 242 may include multiple transmittersthat may be discrete components or combined/integrated components,and/or the receiver 244 may include multiple receivers that may bediscrete components or combined/integrated components. The wirelesstransceiver 240 may be configured to communicate signals (e.g., withTRPs and/or one or more other devices) according to a variety of radioaccess technologies (RATs) such as 5G New Radio (NR), GSM (Global Systemfor Mobiles), UMTS (Universal Mobile Telecommunications System), AMPS(Advanced Mobile Phone System), CDMA (Code Division Multiple Access),WCDMA (Wideband CDMA), LTE (Long-Term Evolution), LTE Direct (LTE-D),3GPP LTE-V2X (PC5), V2C (Uu), IEEE 802.11 (including IEEE 802.11p),WiFi, WiFi Direct (WiFi-D), Bluetooth®, Zigbee, 5G CV2X (Sidelink), UWB,5G ProSe, etc. New Radio may use mm-wave frequencies and/or sub-6 GHzfrequencies. The wired transceiver 250 may include a transmitter 252 anda receiver 254 configured for wired communication, e.g., with the NG-RAN135 to send communications to, and receive communications from, the gNB110 a, for example. The transmitter 252 may include multipletransmitters that may be discrete components or combined/integratedcomponents, and/or the receiver 254 may include multiple receivers thatmay be discrete components or combined/integrated components. The wiredtransceiver 250 may be configured, e.g., for optical communicationand/or electrical communication. The transceiver 215 may becommunicatively coupled to the transceiver interface 214, e.g., byoptical and/or electrical connection. The transceiver interface 214 maybe at least partially integrated with the transceiver 215.

The user interface 216 may comprise one or more of several devices suchas, for example, a speaker, microphone, display device, vibrationdevice, keyboard, touch screen, etc. The user interface 216 may includemore than one of any of these devices. The user interface 216 may beconfigured to enable a user to interact with one or more applicationshosted by the UE 200. For example, the user interface 216 may storeindications of analog and/or digital signals in the memory 211 to beprocessed by DSP 231 and/or the general-purpose processor 230 inresponse to action from a user. Similarly, applications hosted on the UE200 may store indications of analog and/or digital signals in the memory211 to present an output signal to a user. The user interface 216 mayinclude an audio input/output (I/O) device comprising, for example, aspeaker, a microphone, digital-to-analog circuitry, analog-to-digitalcircuitry, an amplifier and/or gain control circuitry (including morethan one of any of these devices). Other configurations of an audio I/Odevice may be used. Also or alternatively, the user interface 216 maycomprise one or more touch sensors responsive to touching and/orpressure, e.g., on a keyboard and/or touch screen of the user interface216.

The SPS receiver 217 (e.g., a Global Positioning System (GPS) receiver)may be capable of receiving and acquiring SPS signals 260 via an SPSantenna 262. The antenna 262 is configured to transduce the wirelesssignals 260 to wired signals, e.g., electrical or optical signals, andmay be integrated with the antenna 246. The SPS receiver 217 may beconfigured to process, in whole or in part, the acquired SPS signals 260for estimating a location of the UE 200. For example, the SPS receiver217 may be configured to determine location of the UE 200 bytrilateration using the SPS signals 260. The general-purpose processor230, the memory 211, the DSP 231 and/or one or more specializedprocessors (not shown) may be utilized to process acquired SPS signals,in whole or in part, and/or to calculate an estimated location of the UE200, in conjunction with the SPS receiver 217. The memory 211 may storeindications (e.g., measurements) of the SPS signals 260 and/or othersignals (e.g., signals acquired from the wireless transceiver 240) foruse in performing positioning operations. The general-purpose processor230, the DSP 231, and/or one or more specialized processors, and/or thememory 211 may provide or support a location engine for use inprocessing measurements to estimate a location of the UE 200.

The UE 200 may include the camera 218 for capturing still or movingimagery. The camera 218 may comprise, for example, an imaging sensor(e.g., a charge coupled device or a CMOS imager), a lens,analog-to-digital circuitry, frame buffers, etc. Additional processing,conditioning, encoding, and/or compression of signals representingcaptured images may be performed by the general-purpose processor 230and/or the DSP 231. Also or alternatively, the video processor 233 mayperform conditioning, encoding, compression, and/or manipulation ofsignals representing captured images. The video processor 233 maydecode/decompress stored image data for presentation on a display device(not shown), e.g., of the user interface 216.

The position (motion) device (PMD) 219 may be configured to determine aposition and possibly motion of the UE 200. For example, the PMD 219 maycommunicate with, and/or include some or all of, the SPS receiver 217.The PMD 219 may also or alternatively be configured to determinelocation of the UE 200 using terrestrial-based signals (e.g., at leastsome of the signals 248) for trilateration, for assistance withobtaining and using the SPS signals 260, or both. The PMD 219 may beconfigured to use one or more other techniques (e.g., relying on theUE's self-reported location (e.g., part of the UE's position beacon))for determining the location of the UE 200, and may use a combination oftechniques (e.g., SPS and terrestrial positioning signals) to determinethe location of the UE 200. The PMD 219 may include one or more of thesensors 213 (e.g., gyroscope(s), accelerometer(s), magnetometer(s),etc.) that may sense orientation and/or motion of the UE 200 and provideindications thereof that the processor 210 (e.g., the general-purposeprocessor 230 and/or the DSP 231) may be configured to use to determinemotion (e.g., a velocity vector and/or an acceleration vector) of the UE200. The PMD 219 may be configured to provide indications of uncertaintyand/or error in the determined position and/or motion.

Referring also to FIG. 3 , an example of a TRP 300 of the BSs (e.g., gNB110 a, gNB 110 b, ng-eNB 114) comprises a computing platform including aprocessor 310, memory 311 including software (SW) 312, a transceiver315, and (optionally) an SPS receiver 317. The processor 310, the memory311, the transceiver 315, and the SPS receiver 317 may becommunicatively coupled to each other by a bus 320 (which may beconfigured, e.g., for optical and/or electrical communication). One ormore of the shown apparatus (e.g., a wireless interface and/or the SPSreceiver 317) may be omitted from the TRP 300. The SPS receiver 317 maybe configured similarly to the SPS receiver 217 to be capable ofreceiving and acquiring SPS signals 360 via an SPS antenna 362. Theprocessor 310 may include one or more intelligent hardware devices,e.g., a central processing unit (CPU), a microcontroller, an applicationspecific integrated circuit (ASIC), etc. The processor 310 may comprisemultiple processors (e.g., including a general-purpose/applicationprocessor, a DSP, a modem processor, a video processor, and/or a sensorprocessor as shown in FIG. 2 ). The memory 311 is a non-transitorystorage medium that may include random access memory (RAM)), flashmemory, disc memory, and/or read-only memory (ROM), etc. The memory 311stores the software 312 which may be processor-readable,processor-executable software code containing instructions that areconfigured to, when executed, cause the processor 310 to perform variousfunctions described herein. Alternatively, the software 312 may not bedirectly executable by the processor 310 but may be configured to causethe processor 310. e.g., when compiled and executed, to perform thefunctions. The description may refer to the processor 310 performing afunction, but this includes other implementations such as where theprocessor 310 executes software and/or firmware. The description mayrefer to the processor 310 performing a function as shorthand for one ormore of the processors contained in the processor 310 performing thefunction. The description may refer to the TRP 300 performing a functionas shorthand for one or more appropriate components of the TRP 300 (andthus of one of the BSs) performing the function. The processor 310 mayinclude a memory with stored instructions in addition to and/or insteadof the memory 311. Functionality of the processor 310 is discussed morefully below.

The transceiver 315 may include a wireless transceiver 340 and a wiredtransceiver 350 configured to communicate with other devices throughwireless connections and wired connections, respectively. For example,the wireless transceiver 340 may include a transmitter 342 and receiver344 coupled to one or more antennas 346 for transmitting (e.g., on oneor more uplink channels and/or one or more downlink channels) and/orreceiving (e.g., on one or more downlink channels and/or one or moreuplink channels) wireless signals 348 and transducing signals from thewireless signals 348 to wired (e.g., electrical and/or optical) signalsand from wired (e.g., electrical and/or optical) signals to the wirelesssignals 348. Thus, the transmitter 342 may include multiple transmittersthat may be discrete components or combined/integrated components,and/or the receiver 344 may include multiple receivers that may bediscrete components or combined/integrated components. The wirelesstransceiver 340 may be configured to communicate signals (e.g., with theUE 200, one or more other UEs, and/or one or more other devices)according to a variety of radio access technologies (RATs) such as 5GNew Radio (NR), GSM (Global System for Mobiles), UMTS (Universal MobileTelecommunications System), AMPS (Advanced Mobile Phone System), CDMA(Code Division Multiple Access), WCDMA (Wideband CDMA), LTE (Long-TermEvolution). LTE Direct (LTE-D), 3GPP LTE-V2X (PC5), IEEE 802.11(including IEEE 802.11p), WiFi, WiFi Direct (WiFi-D), Bluetooth®,Zigbee, UWB, etc. The wired transceiver 350 may include a transmitter352 and a receiver 354 configured for wired communication, e.g., withthe network 140 to send communications to, and receive communicationsfrom, the LMF 120 or other network server, for example. The transmitter352 may include multiple transmitters that may be discrete components orcombined/integrated components, and/or the receiver 354 may includemultiple receivers that may be discrete components orcombined/integrated components. The wired transceiver 350 may beconfigured, e.g., for optical communication and/or electricalcommunication.

The configuration of the TRP 300 shown in FIG. 3 is an example and notlimiting of the disclosure, including the claims, and otherconfigurations may be used. For example, the description hereindiscusses that the TRP 300 is configured to perform or performs severalfunctions, but one or more of these functions may be performed by theLMF 120 and/or the UE 200 (i.e., the LMF 120 and/or the UE 200 may beconfigured to perform one or more of these functions).

Referring also to FIG. 4 , an example server, such as the LMF 120,comprises a computing platform including a processor 410, memory 411including software (SW) 412, and a transceiver 415. The processor 410,the memory 411, and the transceiver 415 may be communicatively coupledto each other by a bus 420 (which may be configured, e.g., for opticaland/or electrical communication). One or more of the shown apparatus(e.g., a wireless interface) may be omitted from the server 400. Theprocessor 410 may include one or more intelligent hardware devices,e.g., a central processing unit (CPU), a microcontroller, an applicationspecific integrated circuit (ASIC), etc. The processor 410 may comprisemultiple processors (e.g., including a general-purpose/applicationprocessor, a DSP, a modem processor, a video processor, and/or a sensorprocessor as shown in FIG. 2 ). The memory 411 is a non-transitorystorage medium that may include random access memory (RAM)), flashmemory, disc memory, and/or read-only memory (ROM), etc. The memory 411stores the software 412 which may be processor-readable,processor-executable software code containing instructions that areconfigured to, when executed, cause the processor 410 to perform variousfunctions described herein. Alternatively, the software 412 may not bedirectly executable by the processor 410 but may be configured to causethe processor 410, e.g., when compiled and executed, to perform thefunctions. The description may refer to the processor 410 performing afunction, but this includes other implementations such as where theprocessor 410 executes software and/or firmware. The description mayrefer to the processor 410 performing a function as shorthand for one ormore of the processors contained in the processor 410 performing thefunction. The description may refer to the server 400 (or the LMF 120)performing a function as shorthand for one or more appropriatecomponents of the server 400 performing the function. The processor 410may include a memory with stored instructions in addition to and/orinstead of the memory 411. Functionality of the processor 410 isdiscussed more fully below.

The transceiver 415 may include a wireless transceiver 440 and a wiredtransceiver 450 configured to communicate with other devices throughwireless connections and wired connections, respectively. For example,the wireless transceiver 440 may include a transmitter 442 and receiver444 coupled to one or more antennas 446 for transmitting (e.g., on oneor more downlink channels) and/or receiving (e.g., on one or more uplinkchannels) wireless signals 448 and transducing signals from the wirelesssignals 448 to wired (e.g., electrical and/or optical) signals and fromwired (e.g., electrical and/or optical) signals to the wireless signals448. Thus, the transmitter 442 may include multiple transmitters thatmay be discrete components or combined/integrated components, and/or thereceiver 444 may include multiple receivers that may be discretecomponents or combined/integrated components. The wireless transceiver440 may be configured to communicate signals (e.g., with the UE 200, oneor more other UEs, and/or one or more other devices) according to avariety of radio access technologies (RATs) such as 5G New Radio (NR),GSM (Global System for Mobiles), UMTS (Universal MobileTelecommunications System), AMPS (Advanced Mobile Phone System), CDMA(Code Division Multiple Access), WCDMA (Wideband CDMA), LTE (Long-TermEvolution). LTE Direct (LTE-D), 3GPP LTE-V2X (PC5), IEEE 802.11(including IEEE 802.11p), WiFi, WiFi Direct (WiFi-D), Bluetooth®,Zigbee, UWB, etc. The wired transceiver 450 may include a transmitter452 and a receiver 454 configured for wired communication, e.g., withthe NG-RAN 135 to send communications to, and receive communicationsfrom, the TRP 300, for example. The transmitter 452 may include multipletransmitters that may be discrete components or combined/integratedcomponents, and/or the receiver 454 may include multiple receivers thatmay be discrete components or combined/integrated components. The wiredtransceiver 450 may be configured, e.g., for optical communicationand/or electrical communication.

The configuration of the server 400 shown in FIG. 4 is an example andnot limiting of the disclosure, including the claims, and otherconfigurations may be used. For example, the wireless transceiver 440may be omitted. Also or alternatively, the description herein discussesthat the server 400 is configured to perform or performs severalfunctions, but one or more of these functions may be performed by theTRP 300 and/or the UE 200 (i.e., the TRP 300 and/or the UE 200 may beconfigured to perform one or more of these functions).

Referring to FIG. 5 , an example of a diagram of a round trip timemeasurement session 500 is shown. The general approach includes aninitiating station 502 and a responding station 504. The initiatingstation 502 and the responding station 504 may be a UE such as the UE200, or other wireless device configured to participate intime-of-flight based positioning. In an example, and not a limitation,the RTT measurement session 500 may be based on Fine Timing Measurementmessages exchanged between the initiating and responding stations 502,504. Other messages and signals such as positioning reference signals(PRS), sounding reference signals (SRS), Infra-Red camera signals, orother reference signals may be used to determine time-of-flightinformation between two UEs. The RTT session 500 may utilize a FTMProtocol (e.g., 802.11mc D4.3 section 10.24.6) to enable two stations toexchange round trip measurement frames (e.g., FTM frames). Theinitiating station 502 may request a positioning session and compute theround trip time by recording the TOA (i.e., t2) of the FTM frame fromthe responding station 504 and recording the TOD of an acknowledgementframe (ACK) of the FTM frame (i.e., t3). The responding station 504 mayrecord the TOD of the FTM frame (i.e., t1) and the TOA of the ACKreceived from initiating station 502 (i.e., t4). The initiating station502 may receive the time ‘t4’ in subsequent FTM messages (e.g.,FTM2(t1,t4). Variations of message formats may enable the timing valuesto be transferred between the initiating and responding stations 502,504. The RTT is thus computed as:

RTT=[(t4−t1)−(t3−t2)]  (1)

The RTT session 500 may allow the initiating station 502 to obtain itsrange with the responding station 504 (e.g., the range is equal to RTT/2times the speed of light). An FTM session is an example of a rangingtechnique between the initiating station 502 and the responding station504. Other ranging techniques such as TDOA, TOA/TOF may also be used todetermine the relative positions of the two stations. Other signalingmay also be used to enable a negotiation process, the measurementexchange(s), and a termination process. For example, Wi-Fi 802.11azranging NDP and TP Ranging NDP sessions may also be used.

Referring to FIG. 6 , a diagram 600 of an example proximity measurementis shown. The diagram 600 includes a first mobile device 602 and anassociated first user 602 a, and a second mobile device 604 and anassociated second user 604 a. The mobile devices 602 and 604 maycorrespond to a cellphone, smartphone, smartwatch, smart glasses,laptop, tablet, PDA, tracking device, navigation device, IoT device,asset tracker, health monitors, wearable trackers, or some otherportable or moveable wireless nodes configured for wirelesscommunications. In an embodiment, one or both of the mobile devices 602,604 may be stationary wireless nodes such as an AP. A barrier detectionapplication may establish a contact range 606 based on the effectiverange of a wireless technology. The mobile devices 602, 604 may exchangeRF signals 610 to determine a range between the users 602 a, 604 a. TheRF signals may be based on existing wireless technologies such as, forexample, IEEE 802.11 (including IEEE 802.11p), WiFi, WiFi Direct(WiFi-D), Bluetooth®, Zigbee, 5G NR, side link protocols, UWB, and otherdevice-to-device (D2D) interfaces. In an example, the RF signals 610 mayinclude messages for a ranging technique (e.g., RTT, TDOA, TOA) and/orfor determining a signal strength measurement (e.g., RSSI). In anexample, the mobile devices 602, 604 may be configured to determineangle-of-arrival (AoA) information of the received RF signals 610. TheRF signals 610 may be used to perform a range measurement to determinethe distance between the first and second mobile devices 602, 604. Themobile devices 602, 604 may be configured to report the presence of oneanother to a network, to one or more applications executing on thedevices 602, 604, and/or notify a respective user 602 a, 604 a via auser interface.

Referring to FIG. 7 , with further reference to FIG. 6 , a diagram 700of an example proximity measurement through a barrier 702 is shown. Asdepicted in the diagram 700, the barrier 702 is disposed between thefirst user 602 a with the first mobile device 602, and the second user604 a with the second mobile device 604. The barrier 702 may be a wall,window, floor, ceiling or other object disposed between two users. Forexample, groups of objects may also act as barriers, such as traffic ina roadway, cars in a parking lot, people, a crowded bookshelf in alibrary, shelves in a grocery store or other aisle configurations suchthat the density and/or compositions of the objects may attenuate RFsignals. The mobile devices 602, 604 may exchange RF signals 710 throughthe barrier 702, however, the barrier 702 may cause some signalattenuation 710 a (e.g., reflection, refraction, absorption) of the RFsignals 710. The physical attributes of the barrier 702 (e.g.,dimensions, material composition, orientation, etc.) will impact theamount of the attenuation 710 a of the RF signals 710 and thus willimpact the strength of the RF signals 710 received by the mobile devices602, 604. In general, the barrier 702 will not impact the time-of-flight(e.g., RTT, TDOA, TOA/TOD) based range measurements. The mobile devices602, 604 may be configured to compare the range measurements with thesignal strength measurements to detect the presence of the barrier 702.For example, a differential between an expected RSSI signal and the RTTbased range measurement may be proportional to a probability that the RFsignals 710 are travelling through the barrier 702. That is, theexpected RSSI signal may be based on known signal propagation models(e.g., shadowing model). In an example, the range ‘d’ based on an RSSImay be determined based on a propagation equation such as:

log 10d=[L−20 log 10(5745)+28]/24  (2)

-   -   where, d is the range; and    -   L is the path loss (e.g., L=23 dBm−<RSSI value>).

A wireless node may utilize an indication that a barrier is present tomodify the functionality of local applications in a variety of usecases. For example, the mobile devices 602, 604 may be configured toreport the presence of a barrier to a network, to one or moreapplications executing on the mobile devices 602, 604, and/or notify arespective user 602 a, 604 a via a user interface.

Referring to FIG. 8 , a graphical example of a probability function fordetecting a barrier with radio frequency signals is shown. A graph 800includes a range axis 802 (in meters (m)) and a signal strength axis 804(in decibel-milliwatts (dBm)). An example probability function 806 isplotted on the graph 800 to demonstrate the probable signal loss andgrowing uncertainty as a function of the range. The probability function806, and the associated range and signal strength values are examples,and not limitations, as other probability functions may also begenerated based on empirical observations and used to detect andclassify a barrier. In an example, the range values may be based on RFsignal measurements such as RTT based ranges and the probabilityfunction 806 may be a correlation of RTT based ranges and thecorresponding RSSI measurements. Referring to FIG. 6 , the RF signals610 may correspond to a first measurement point 808 indicating a rangeof 2 m and a RSSI measurement of approximately −25 dBm. The RSSImeasurement value for the first measurement point 808 is within, orgreater than, the probability function 806 and thus indicates that nobarrier is present between the mobile devices 602, 604. In contrast,referring to FIG. 7 , the RF signals 710 may correspond to a secondmeasurement point 810 indicating a range of 2 m and a RSSI measurementof approximately −70 dBm. The RSSI measurement value for the secondmeasurement point 810 is less than the probability function 806 and thusindicates the presence of a barrier (i.e., the barrier 702) between themobile devices 602, 604.

In an embodiment, the probability function 806 may be expressed as:

P(Barrier)∝Δ(RangeEst_(rssi),RangeEst_(t_flight))  (3)

where the Δ function provides a metric of difference between the rangeestimates based on two relative positioning techniques. The metric maybe binned (e.g., histogram bin) and the bin sizes may be implementationspecific. In an example, the probability function may be expressed usinga Bayesian estimation:

$\begin{matrix}{{P\left( {{Barrier}❘d} \right)} = \frac{{P\left( {d❘{Barrier}} \right)}*{P({Barrier})}}{P(d)}} & (4)\end{matrix}$

-   -   where ‘d’ is an indication of a metric falling in the d^(th)        bin;    -   P(d|Barrier) may be measured by empirical data;    -   P(Barrier) is the Apriori probability that two devices have a        barrier between them;    -   P(d) is the Apriori probability of difference metric        corresponding to the measured value.        In an embodiment, the probability function 806 may be based on        crowdsourced empirical data provided to one or more network        servers from a large number of devices in a wireless network. In        an example, one or both of the mobile devices 602, 604 may be        configured to provide the RTT and RSSI range measurements and        their current locations to a crowdsourcing server. Other        information associated with a potential barrier such as an        optical image (e.g., via a camera) or radio frequency (RF)        sensing information, ultrasound measurements, or other        measurements based on the capability of the mobile device may be        provided to the crowdsourcing server.

Referring to FIG. 9 , a graph 900 of example barrier scenarios is shown.The barrier scenarios and corresponding measurement values are examplesand not limitations as other materials and measurements may be used toderive probability functions and classification models. The graph 900includes an indicated range axis 902 and a RSSI measurement axis 904.The indicated ranges are based on RTT measurements through the indicatedbarrier and the RSSI measurements represent the average RSSI over 5seconds of logging. As indicated in the graph 900, the RSSI measurementsmay be significantly impacted based on the barrier material. Asexpected, denser structures such as concrete attenuate the RF signalsmore than less dense structures such as an internal door. A probabilityfunction may be generated based on large samples of different barrierscenarios and used to predict the presence and classification of abarrier based on the ranging and signal strength measurements. In anexample, RF signals may be measured in different frequency layers andthe corresponding differences in attenuation may be used to furtherclassify a barrier. In an embodiment, machine learning techniques may beused to further characterize the time based range measurement and signalstrength measurements based on the composition of the barrier.

Referring to FIGS. 10A and 10B, an example vehicle locking and unlockingsystem utilizing barrier detection is shown. In general, the number ofvehicle manufacturers using digital keys (e.g., key fobs) for access isincreasing year over year. Vehicles may be configured to automaticallyprovide access to the user based on the proximity of the digital key. Insuch use cases, detecting a barrier type is helpful in distinguishingbetween situations when the user is located next to a vehicle without abarrier, or situations when a barrier comprised of glass (e.g., avehicle window) is between the user and a transceiver in the vehicle andwhen a more substantial barrier such as concrete or wood (e.g., floor,garage door, etc.) is disposed between the user and the vehicle. The RTTand RSSI techniques described herein may reduce false positives whichmay occur with the previous RSSI based digital key techniques. Forexample, a first diagram 1000 depicts a UE 1002 (e.g., smartphone, keyfob, etc.) configured to enable a user 1002 a to provide key informationto lock or unlock a vehicle 1004. The vehicle 1004 may include awireless node (not shown in FIG. 10A) configured to send and receive RFsignals. In an example, the UE 1002 and the vehicle 1004 may exchange RFsignals 1006 to determine a range between them. The RF signals may bebased on existing wireless technologies such as, for example, IEEE802.11 (including IEEE 802.11p, 802.11mc, 802.11az), WiFi, WiFi Direct(WiFi-D), Bluetooth®, Zigbee, 5G NR, side link protocols, UWB, and otherdevice-to-device (D2D) interfaces. The RF signals 1006 may includemessages for a ranging technique (e.g., RTT, TDOA. TOA) and/or fordetermining a signal strength measurement (e.g., RSSI). For example,Wi-Fi 802.11az ranging NDP and TP Ranging NDP sessions may be used. Inan example, the UE 1002 and/or the vehicle 1004 may be configured todetermine the AoA of the received RF signals 1006. When the UE 1002 iswithin an established range threshold, the lock/unlock functions on thevehicle 1004 are enabled.

In a second diagram 1020, a barrier 1022 is disposed between the user1002 a and the vehicle 1004. The UE 1002 and the vehicle 1004 mayexchange RF signals 1024 through the barrier 1022, but the barrier 1022may cause some signal attenuation 1024 a (e.g., reflection, refraction,absorption) of the RF signals 1024. The material composition and otherphysical features of the barrier 1022 (e.g., dimensions, orientation,etc.) will impact the amount of the attenuation 1024 a of the RF signals1024 and thus will impact the strength of the RF signals 1024 receivedby the UE 1002 and the vehicle 1004. In an example, if a differencebetween an RTT based distance measurement and a RSSI based measurementis above a threshold value, the lock/unlock function in the vehicle willbe disabled (e.g., the user 1002 a will be denied entry to the vehicle1004). In an example, a second threshold value for the differencebetween RTT and RSSI distance measurements may be based on theattenuation caused by the presence of a window in the vehicle. Thus, thedifference in the distance measurements may be used to detect whether avehicle window is open or closed. The threshold values may be stored ina data structure, such as a look-up-table (LUT), in local memory in theUE 1002 or the vehicle 1004. In an example, the threshold values may beassociated with a AoA measurement performed by the vehicle 1004 toenable different threshold values for different lines of approach to thevehicle. The threshold values in the LUT may be established duringvehicle manufacturing and/or periodic calibration procedures.

Referring to FIG. 10C, with further reference to FIG. 10B, a method 1050for granting access to the vehicle 1004 based in part on barrierdetection information includes the stages shown. The method 1050 is,however, an example and not limiting. The method 1050 may be altered,e.g., by having stages added, removed, rearranged, combined, performedconcurrently, and/or having single stages split into multiple stages. Inan example, the vehicle 1004 may include a wireless node, such as the UE200 or the TRP 300, configured to perform the barrier detectiontechniques described herein. The vehicle 1004 is an example, and not alimitation, as the method 1050 may be used with other locking andsecurity mechanisms. For example, the method 1050 may be used forgranting access to a room, a storage box, activating a kiosk, accessingan Automated Teller Machine (ATM), or other areas or entities where auser's presence should be verified before granting access to the area orentity.

At stage 1052, the method includes determining a distance value “d”based on RTT or other ToF measurements, and a delta RSSI value. A TRP300, including a processor 310 and a wireless transceiver 340, are ameans for determining the distance value and the delta RSSI value. TheUE 1002 and the vehicle 1004 are configured to obtain ToF and RSSIinformation based on an exchange of RF signals 1024. In an example, theTRP 300 in the vehicle 1004 is configured to determine an estimated RSSIvalue based on the distance value “d” obtained via a ToF technique(e.g., equation 2). The TRP 300 may measure the RSSI of the RF signals1024 and determine the delta RSSI value based on the difference betweenthe estimated and measured RSSI values.

At stage 1054, the method includes determining if the distance value “d”is less than a distance threshold value. The processor 310 is a meansfor comparing the distance value to a threshold. In an example, the ToFbased distance measurement may be sufficient to determine that the UE1002 is too far away from the vehicle 1004 to allow access. The distancethreshold value may be a static value (e.g., 1 m, 2 m, 5 m, etc.) andthe vehicle may be configured to remain locked until the user 1002 a iswithin the threshold value. In an example, the distance threshold valuemay be based on other context information such as the location of thevehicle, the time of day, and/or an idle duration (e.g., how long hasthe vehicle been parked). For example, the distance threshold value maybe decreased when the vehicle is located in a shopping area parking lot.The distance threshold values and context information may persist in adata structure (e.g., LUT) in the memory 311. If the distance value isgreater than the distance threshold value, access to the vehicle isdenied at stage 1056.

At stage 1058, the method includes determining if the delta RSSI valueis less than a threshold value. The processor 310 is a means forcomparing the delta RSSI value to a threshold value. In an example,referring to FIG. 9 , one or more threshold values may be associatedwith different barrier types. The threshold value may be used to denyaccess if the barrier is of one type (e.g., concrete, wood) and enableaccess if the barrier is of another type (e.g., glass). For example, thethreshold value may be associated with 0.4 m concrete wall and accesswill be denied at stage 1060 if the delta RSSI value is greater than thethreshold value, or allowed at stage 1062 if the delta RSSI value isless than the threshold value.

Referring to FIG. 11 , an example use case diagram 1100 for generatingindoor maps based in part on barrier detection information is shown. Thediagram 1100 includes an indoor area 1120 including a plurality ofbarriers such as walls and doors. In an example, the indoor area 1120may include one or more wireless nodes, such as an AP 1106, configuredto communicate with UEs and other devices located in or near the indoorarea 1120 via radio access technologies as described herein. Inoperation, a plurality of users 1102 a-c may carry respective UEs asthey traverse around the indoor area 1120. For example, a first user1102 a may have travelled along a first path 1104 a, a second user 1102b may have travelled along a second path 1104 b, and a third user 1102 cmay have travelled along a third path 1104 c. While the users 1102 a-care within range of the AP 1106, and/or one another, their UEs may beconfigured to exchange RF signals 1112 a-c with the AP 1106 and/or toexchange RF signals 1114 a-c with the other UEs in and around the indoorarea 1120. The AP 1106 may obtain RTT and RSSI measurement valuesperiodically (e.g., 0.5 sec, 1 sec, 2 secs, 5 secs, etc.) and report themeasurement values to a location server 1110. The UEs may alsoperiodically obtain RTT and RSSI measurement values (e.g., based onexchanges with one another or other wireless nodes) and report themeasurement values to the AP 1106. Since the users 1102 a-c, and moreparticularly their UEs, may regularly traverse the indoor ara, theresulting RTT and RSSI information associated with the differentlocation for each UE may be fused to provide an indoor map of barriersalong with barrier types. Barrier type detection can be used to detectand distinguish doors from walls because doors are usually made ofdifferent material types as compared to walls. For example, the locationserver 1110 may be configured to apply the barrier detection techniquesdescribed herein to the collected RTT and RSSI measurements to determinethe composition of a wooden door 1108 a (e.g., on a server closet), ametal door 1108 b (e.g., in a stair well), and a glass door 1108 c(e.g., for a conference room). The resulting indoor map may be appliedto a variety of different use cases such as contact tracing, indoornavigation for robots (e.g., cleaning robots, warehouse robots, etc.),assisted navigation for people with disabilities (e.g., locatingexits/entrances). In an example, the RTT and RSSI measurements may beutilized to locate doors and windows and to determine the current stateof a barrier (e.g., open and closed). The state information may beapplied to routing algorithms (e.g., to prioritize paths with open doorsover paths with closed doors). Other mapping applications may alsoutilize the barrier detection information.

Referring to FIG. 12 , a diagram 1200 of an example use case forimproving a network typology based on barrier type information is shown.Detecting barrier material types may be helpful in optimizing the numberof APs needed in a particular building. For example, a building 1202 mayhave one or more structural walls 1208 a-b which may attenuate signalsfrom an AP 1204. One or more UEs 1206 a-b in the building 1202 may beconfigured to exchange RF signals with the AP 1204 to determine barriertype information based on RTT and RSSI information as described herein.In an example, such barrier material type information may be used todetermine whether to remove redundant APs which cover an area whichalready includes strong RF signals. Conversely, the barrier materialtype information may be used to add APs to areas which have poor signalcoverage. For example, the measurements obtained by the UEs 1206 a-b intheir respective locations, and the resulting barrier type informationassociated with the walls 1208 a-b, may lead to a decision to addadditional APs 1210 a-b as depicted in FIG. 12 . The barrier typeinformation may also help optimize transmit power to reduce powerconsumption, improve coverage, and maximize throughput of the network.In an example, the barrier type information may also be used topurposely generate a space that has less or no signal coverage in orderto reduce RF signal interference within that space.

Referring to FIGS. 13A and 13B, diagrams of an example use case forusing barriers to improve network throughput are shown. Popular venues,such as convention halls, sports arenas, theme parks, etc. may haveseveral nodes to provide wireless services to users in the venue. Forexample, a venue 1302 may have a first AP 1304 with a first coverageboundary 1304 a, and a second AP 1306 with a second coverage boundary1306 a. The coverage areas of the APs 1304, 1306 may overlap to ensureadequate wireless services to a plurality of users in the venue 1302.The overlapping coverage areas, however, may cause throughput issues forthe network as the UEs in one of the coverage areas may attempt to use asingle AP. Thus, one of the two APs is servicing an excess number UEswhile the other AP is servicing fewer UEs. The excess number of UEs maycause unnecessary latency issues for the UEs. In an example, a physicalbarrier 1308 may be disposed within the overlapping coverage areas tobifurcate the area such that an equal number of users may be serviced byeach AP. Referring to FIG. 13B, the physical barrier 1308 may beconstructed with appropriate dimensions and material properties to limitthe coverage areas of the APs 1304, 1306 to their respective sides ofthe physical barrier 1308. For example, the physical barrier 1308 may beconfigured to reduce the RSSI of signals transiting the barrier by −100dBm. The presence of the physical barrier 1308 may, for example, reducethe coverage area of the first AP 1304 to a third coverage boundary1314, and reduce the coverage area of the second AP 1306 to a fourthcoverage boundary 1316. The dimensions of the coverage boundaries 1314,1316 are examples, and not limitations, as the actual overlap betweenthe areas may vary based on other possible signal paths in the venue1302. Other materials and barrier configurations may also be used toreduce the coverage area(s) of one or more wireless nodes.

The physical barrier 1308 may be one or more temporary structures whichmay be relocated within the venue 1302 to achieve the desired balance ofcoverage and throughput for the respective APs. In an example, thephysical barrier 1308 may be comprised of material(s) (e.g., set ofantennas) configured to change the attenuation properties of barrier. Inan example, a controller 1310 may include a near field communications(NFC) device configured to be used with a proximate UE to control theattenuation caused by the physical barrier 1308. The controller 1310 maybe configured to communicate with one or more APs (e.g., via WiFi, BT,etc.) to receive control information. For example, UEs in the venue 1302may be configured to report their respective RSSI measurements to thecontroller 1310, and the controller 1310 may be configured to modify thebarrier attenuation properties (e.g., modify the RF power to the set ofantennas in the barrier 1308) to achieve the desired bifurcation of thecoverage areas.

Referring to FIGS. 14A and 14B, diagrams of example use cases fordevice-to-device (D2D) data sharing are shown. In a first diagram 1400,a first UE 1402 (associated with a first user 1402 a) is sharing datawith a second UE 1404 (associated with a second user 1404 a) via awireless link 1406. The wireless link 1406 may be WiFi, BT, UWB, orother sidelinks described herein configured for D2D data sharing. Forexample, the first user 1402 a may desire to send the second user 1404 aphotograph, payment information, or other confidential information viathe wireless link 1406. The barrier type detection techniques describedherein may be utilized to help categorize proximate devices based on thecorresponding RTT and RSSI information. For example, to distinguishbetween wireless nodes which are within line-of-sight (e.g., nobarrier), wireless nodes which are behind ‘heavy’ barriers (e.g., walls,doors) and wireless nodes that are behind ‘light’ barriers (e.g., humanbody, backpack, table, etc.). Such barrier type information may behelpful to identify the intended devices for data sharing and pairing,especially for secure applications such as providing secure paymentinformation. For example, referring to FIG. 14B, a second diagram 1420includes an unseen attacker 1424 a lurking behind a barrier 1422. Theattacker is utilizing a third UE 1424 to attempt to initiate orotherwise intercept confidential information from the first user 1402 avia a message exchange 1426 with the first UE 1402. In an example, thefirst UE 1402 may be configured to compare the RTT and RSSI informationfor the message exchange 1426 to detect the presence of the barrier 1422(e.g., based on the attenuation 1426 a), and halt any data exchangebased on the detection of the barrier 1422. The reaction to thedetection of a barrier may vary. For example, a threshold value such asdescribed in FIG. 10C may be used to distinguish between ‘heavy’ and‘light’ barriers such that the presence of a light barrier may notimpede the data transfer.

Referring to FIGS. 15A and 15B, diagrams of example use cases forutilizing barrier detection in a home network are shown. In a firstdiagram 1500, a home 1502 may include a plurality of wireless nodes,such as an AP 1504 and mobile devices including a first UE 1514, asecond UE 1518, a vehicle 1512, and an outdoor camera 1510. Each of thewireless nodes in the first diagram 1500 are configured to communicatewirelessly via WiFi, BT, UWB, or other radio access technologies asdescribed herein. The AP 1504 may be configured to communicate with oneor more control systems in the home 1502. For example, the home mayinclude one or more servers 400 configured to communicate with the AP1504 via wired or wireless connections. In an example, the controlsystems may include an environmental controller 1506, a sound systemcontroller 1508, and/or other controllers configured to controlcomponents in the home 1502. The barrier detection techniques describedherein may be utilized to improve home comfort and security. Forexample, a user may transport the first UE 1514 around differentlocations of home 1502, such as long a trajectory 1516. In a firstposition 1514 a, message exchanges between the UE 1514 and the AP 1504may detect a first window 1520 a. Message exchanges at a second position1514 b may detect a second window 1520 b. Message exchanges between thesecond UE 1518 and the first UE 1514 at a third position 1514 c maydetect a third window 1520 c. Message exchanges between the AP 1504 andthe outdoor camera 1510 may also be used to detect the third window 1520c. Message exchanges between the AP 1504 and the vehicle 1512 may beused to detect a door 1522. The AP 1504, and other wireless nodes in thehome 1502, may be configured to report the barrier detection informationto a server 400 to enable the detection of state changes in the home.For example, variations in the detected barrier type information may beused to determine if a window or door are in an open or closed state.The barrier state information may then be used to help identifycontextual information and how it applies to a user. The barrier stateinformation may be utilized to identify when a door or a window is in anopen or a closed state, which may be used as a factor in adjusting adevice's parameters or identifying a user's preferences. For example, ifthe door 1522 is in a closed state, the user may enable the sound systemcontroller 1508 to utilize a first speaker volume setting, whereas ifthe door is in an open state, the sound system controller 1508 mayutilize a second speaker volume setting, or switch to a headphonesetting. In an example, the environmental controller 1506 may beconnected to a weather service and a thermostat device in the home 1502,and configured to activate a climate control (e.g., heat,air-conditioning) based on the state of the doors and windows, and otheruser preferences and/or historic routines. In an example, the RTT andRSSI based information may also be used in combination with RF sensinginformation obtained by one or more wireless nodes. For example, the AP1504 may be configured to utilize monostatic and/or bistatic RF sensingtechniques to determine the state of the home 1502.

In an example, referring to FIG. 15B, one or more wireless nodes such asIoT devices may be installed in the home 1502 to detect state changessuch as flooding, intruders, or pests. The home 1502 may include abasement 1552 and a plurality of wireless nodes (e.g., IoT devices) maybe disposed near the floor of the basement to detect flooding. A firstIoT device 1554 a and a second IoT device 1554 b may be configured tosend and receive RF signals with the AP 1504 as described herein. Achange in the RTT and RSSI information associated with a respectivefirst signal 1558 a and a second signal 1558 b may be an indication offlooding in the basement 1552. For example, a water level 1556 may causeattenuation in the signals 1558 a-b. The environmental controller 1506may be configured to receive the RTT and RSSI information from the AP1504 and generate an alert to notify a user (e.g., via the first UE1514) that there is flooding in the basement 1552. Other wireless nodesand barrier type information may also be used to detect a change instate in the home 1502. For example, a change in barrier typeinformation of an outer wall due to termite infestation, carpenter beedamage, or other such pests which can change the density of a structure(e.g., by devouring and/or adding material for a nest) may be detectedbased on the RTT and RSSI information.

Referring to FIGS. 16A and 16B, diagrams of example use cases fordetermining a state of a local environment based in part on barrierdetection techniques are shown. In a first diagram 1600, a vehicleparking structure 1602 includes one or more APs 1604 a-d configured toobtain RTT and RSSI information from one another and/or from othermobile devices traversing through the parking structure 1602. Forexample, a user may carry a UE 1606 along a trajectory 1608 from a firstposition 1610 a to a second position 1610 b. The UE 1606 may beconfigured to exchange messages with one or more of the APs 1604 a-dalong the way. The APs 1604 a-d may be to a server 400 (not shown inFIG. 16A) configured to collect and analyze barrier density informationbased on the signal exchanges. The resulting barrier information may beused to determine a general state (e.g., 10%, 20%, 50%, 80%, etc. ofcapacity) of the parking structure 1602. That is, when fewer vehiclesare present the attenuation of the RF signals between the APs 1604 a-dand the UE 1606 will be less than when there are more vehicles in theparking structure 1602. While FIG. 16A depicts a 2-dimensional (2D)arrangement of APs and UEs, 3-dimensional configurations may be usedwhen a parking structure includes multiple levels. In an example, theAPs 1604 a-d and the UE 1606 may be configured to obtain RF sensingmeasurements to detect the presence of vehicles.

In a second diagram 1650, a warehouse 1652 may include a plurality ofshelving units 1654 a-b and proximate IoT devices 1656 a-f. The IoTdevices may include some or all of the components of a TRP 300 and areconfigured to exchange RF signals with one another and/or other mobiledevices in the warehouse 1652. For example, a pick-and-place robot 1658may be configured to move throughout the warehouse 1652 and/or theshelving units 1654 a-b to place and/or remove inventory from theshelves. The robot 1658 may include one or more transceivers configuredto communicate with the IoT devices 1656 a-f via WiFi, BT, UWB, or otherradio access technologies. For example, the robot 1658 may include afirst transceiver 1658 a in a body section and/or a second transceiver1658 b in an end effector. The RF signals transmitted through theshelving units 1654 a-b may be used to determine the current state ofinventory. For example, a retailer may utilize RTT and RSSI informationdescribed herein for bulk inventory management. Full boxes may bedetected as barrier and indicate a first inventory level. Empty shelvesmay be detected as no barrier to indicate a second inventory level(e.g., low inventory). In an example, the box material type may beutilized to indicate that one or more items are present in the shelvingunits 1654 a-b, whereas empty shelves in the shelving units 1654 a-b aretypically metal which can be classified as a different state (e.g.,associated with empty shelves). The robot 1658 is an example, and not alimitation, as other automated devices (e.g., drones, collaborativebots, mobile racks, roaming shuttles, autonomous mobile robots, sorters,etc.) may be configured to exchange RF signals with one another and/orother wireless nodes, and the corresponding RF signals may be analyzedbased on the RT and RSSI techniques provided herein.

Referring to FIG. 17 , with further reference to FIG. 2 , an exampleframework 1700 diagram of a user equipment for barrier detection isshown. The framework 1700 is an example of a framework utilized by thewireless nodes such as the UEs, APs, and IoT devices described herein.In an example the framework 1700 may include hardware modules such as aGNSS module 1702, a modem module 1704, a WiFi transceiver 1706, asensors module 1708 and a BLUETOOTH (BT) transceiver 1710. The GNSSmodule 1702 may include a SPS receiver 217, the modem module 1704 mayinclude a modem processor 232, the WiFi transceiver 1706 may include awireless transceiver 240, the sensors module 1708 may include a sensorprocessor 234, and the BT transceiver 1710 may include a wirelesstransceiver 240. A drivers layer 1712 may include instructions toconfigure the WiFi transceiver 1706 and/or the BT transceiver to performranging and signal strength measurements. In an example, the UE 200 mayinclude a plurality of transmit and receive antenna pairs and the WiFitransceiver may be configured to determine channel state information(CSI) for the various antenna pairs. In an embodiment, a WiFi Fusionfirmware module 1714 may include hardware and software components toobtain RF signal measurements and reduce the demand on the applicationprocessor (e.g., the general-purpose processor 230). The WiFi Fusionfirmware may interface with a hardware abstraction layer (HAL) 1716. Ahigh-level operating system (HLOS) 1720 may provide an embedded OS toprovide higher level services such as multimedia playback, GraphicalUser Interface (GUI) frameworks including built-in touch screen supportand other features required for mobile device applications. Theframework 1700 is an example and not a limitation as other hardware,drivers and firmware may be used. For example, additional firmwaremodules may include database applications, multi-modal RF fusion,geofencing and history/batching modules. A wireless node may include oneor more secure processors, Trusted Execution Environments, and theframework 1700 may utilize corresponding trusted applications and trustzones for secure processing and exchange of barrier type information.For example, a secure processor may be an ARM Cortex based processor andmay include an ARM TrustZone to enable embedded security options. In anexample, a wireless node may also include hypervisors running onprocessors that support multiple trusted virtual machines that conductsensing operations protected from malware that could run on high leveloperating systems.

Referring to FIG. 18 , with further reference to FIGS. 1-17 , a method1800 for detecting a change in state for a physical environment includesthe stages shown. The method 1800 is, however, an example and notlimiting. The method 1800 may be altered, e.g., by having stages added,removed, rearranged, combined, performed concurrently, and/or havingsingle stages split into multiple stages.

At stage 1802, the method includes determining a first state of aphysical environment based on one or more round trip time measurementsand one or more received signal strength measurements associated with afirst plurality of radio frequency signals exchanged with one or morewireless nodes. A wireless node such as the UE 200, including one ormore processors 210 and a transceiver 215 is a means for determining afirst state of a physical environment. In an example, referring to FIG.15A, wireless nodes such as the UE 1514, the AP 1504, the vehicle 1512and the outdoor camera 1510 may be configured to communicate wirelesslyvia RF signals (e.g., WiFi, BT, UWB, etc.) and obtain RTT and RSSImeasurement values at a first time to determine a first state of aphysical environment (e.g., the home 1502). The RTT and RSSI measurementvalues may be used to detect barriers such as windows and doors betweenthe wireless nodes. In a first state, the windows and door may beclosed. Other use cases may have other possible states. For example, adry basement, full shelves, empty parking lots, etc. may define statesfor their respective physical environments.

At stage 1804, the method includes determining a second state of thephysical environment based on one or more round trip time measurementsand one or more received signal strength measurements associated with asecond plurality of radio frequency signals exchanged with the one ormore wireless nodes. The wireless node including one or more processors210 and a transceiver 215 is a means for determining a second state of aphysical environment. The wireless nodes may be configured to obtainadditional RTT and RSSI measurement values at a second time to determinethe second state of the physical environment. For example, the RTT andRSSI measurement values may detect a change in barrier type such as whena window or door is opened (e.g., not attenuating the RF signals). Otherstate changes such as when water floods a basement, when shelves arefull, partially full, empty, or when vehicles are parked in a lot, andother changes to the physical environment which will cause a change inthe RF signal attenuation as compared to the attenuation caused when thephysical environment is in the first state. In an example, the RTT andRSSI measurement values may be used to determine a barrier typeassociated with a barrier based on the distance between the wirelessnodes and the signal loss. In an example, barrier type information maybe stored in a data structure in local memory and/or networked memorylocations.

At stage 1806, the method includes providing an indication of a statechange in the physical environment based at least in part on acomparison of the first state and the second state. The wireless nodeincluding one or more processors 210 and a transceiver 215 is a meansfor providing an indication of the change in state. In an example, theUE 1514 and/or the AP 1504 may be configured to detect a change in theRSSI measurements for RF signals exchanged with other wireless nodeswhen the relative positions remain constant for the first and secondplurality of RF signal exchanges. AoA measurements and other locationinformation (in addition to the RTT measurements) may also be used todetect state changes in the physical environment. The indication of thestate change may include, for example, a visual, audible, or haptic(e.g., vibration) response configured to alert a user of the statechange (e.g., a notification on the display). Other indications mayinclude providing alerts/messages to other controllers such as theenvironmental controller 1506, the sound system controller 1508, and/orother controllers configured to utilize state information.

Referring to FIG. 19 , with further reference to FIGS. 1-17 , a method1900 for generating mapping information based on barrier detectionincludes the stages shown. The method 1900 is, however, an example andnot limiting. The method 1900 may be altered, e.g., by having stagesadded, removed, rearranged, combined, performed concurrently, and/orhaving single stages split into multiple stages.

At stage 1902, the method includes detecting one or more barriers basedon measurement information associated with a plurality of radiofrequency signals exchanged with one or more wireless nodes, wherein themeasurement information includes round trip time measurements andreceived signal strength measurements. A wireless node such as the UE200, including one or more processors 210 and a transceiver 215 is ameans for detecting one or more barriers. In an example, referring toFIG. 11 , a UE or AP may be configured to obtain RT and RSSI informationfrom a wireless nodes at various locations in the indoor area 1120. Inan example, AoA and/or RF sensing information may also be obtained bythe UEs and APs. The UEs and/or APs may be configured to store the RTT,RSSI, AoA and RF sensing measurement information to determine locationand barrier type information. In an example, a location server 1110 maybe configured to receive and analyze the measurement information.

At stage 1904, the method includes determining a location and a materialcomposition for each of the one or more barriers based at least in parton the round trip time measurements and the received signal strengthmeasurements. The wireless node including one or more processors 210 anda transceiver 215 is a means for determining the location and thematerial composition for each of the one or more barriers. In anexample, referring to FIG. 9 , the difference between range informationassociated with the RTT measurements and the RSSI measurements may beused to determine material composition information. The location of thebarrier may be estimated based on AoA measurements and/or RF sensingmeasurements. In an example, other positioning techniques such asmultilateration with other wireless nodes (e.g., anchor nodes) may beused to establish the locations of the wireless nodes and the estimatedlocations of the one or more barriers (e.g., being located between thewireless nodes). In an example, the location server 1110 may beconfigured to analyze the RTT, RSSI, AoA, RF sensing, and/or otherlocation information to determine the location and material compositionof the one or more barriers.

At stage 1906, the method includes generating mapping information basedon the location and material composition of each of the one or morebarriers. The wireless node including one or more processors 210 is ameans for generating the mapping information. In an example, the mappinginformation may include the estimated locations of walls and doors, suchas the doors 1108 a-c. For example, the wireless node and/or thelocation server 1110 may be configured to apply the barrier detectiontechniques described herein to the collected RTT, RSSI. AoA, and RFsensing measurements to determine the composition of the wooden door1108 a, the metal door 1108 b, and the glass door 1108 c. The generatedmapping information may be applied to different use cases such ascontact tracing, indoor navigation for robots, assisted navigation forpeople with disabilities, or routing information for an emergencyegress. Other mapping applications may utilize the location and materialcomposition information.

Referring to FIG. 20 , with further reference to FIGS. 1-17 , a method2000 for authorizing a device-to-device data exchange based on barrierdetection information includes the stages shown. The method 2000 is,however, an example and not limiting. The method 2000 may be altered,e.g., by having stages added, removed, rearranged, combined, performedconcurrently, and/or having single stages split into multiple stages.

At stage 2002, the method includes receiving a request for a dataexchange from a wireless node. A UE 200, including one or moreprocessors 210 and a transceiver 215 is a means for receiving a requestfor a data exchange. In an example, referring to FIGS. 14A and 14B, theUE 1402 may receive a request to perform a data exchange (e.g., filetransfer, payment information, etc.) via a wireless link from aproximate wireless node such as the second UE 1404 or the third UE 1424.In an example, the data exchange may be an electronic key entry code forentering a vehicle such as describe in FIGS. 10A and 10B. The wirelesslink may utilize WiFi, BT, UWB, or other sidelinks configured for D2Ddata sharing.

At stage 2004, the method includes determining a first range measurementto the wireless node using a first positioning technique. The one ormore processors 210 and the transceiver 215 are a means for determiningthe first range measurement. The first range measurement may be based onRTT techniques such as described in FIG. 5 . For example, the RTTmeasurements may utilize the wireless link established with the wirelessnode. The range to the wireless node may be based on the RTT valuedetermined via equation (1). That is, the range to the first node isequal to the RTT/2 times the speed of light. In an example, the AoA ofRTT messages may also be determined.

At stage 2006, the method includes determining a second rangemeasurement to the wireless node using a second positioning techniquethat is different from the first positioning technique. The one or moreprocessors 210 and the transceiver 215 are a means for determining thesecond range measurement. The second measurement may utilize the RSSI ofthe signals exchanged with the wireless node. In an example, the RSSIvalue may be the expected propagation of the signals (e.g., equation(2)) based on the distance to the wireless node (e.g., the first rangemeasurement obtained at stage 2004), which indicates the wireless nodeis not behind a barrier. In an example, the RSSI value may be less thanthe expected propagation due to attenuation caused by a barrier.

At stage 2008, the method includes allowing or denying the data exchangebased on the first range measurement and the second range measurement.The one or more processors 210 and the transceiver 215 are a means forallowing or denying the data exchange. The data exchange may be deniedif the measured RSSI value is less than the expected RSSI value (e.g.,based on the distance determined with the RTT measurements). Forexample, referring to FIG. 14B, the discrepancy in the first and secondrange measurements may indicate the presence of the barrier 1422. TheRSSI value may be compared to a threshold value to determine whether thebarrier is significant (e.g., a wall, door, etc.) or minor (e.g., abackpack, notebook, etc.). In an example, the threshold value may bebased on a current context of a UE. For example, a trusted environment(e.g., a user's home, office) may have a different threshold value thana public area (e.g., park, campus). The data exchange may be allowed ifthe measured RSSI value meets and expected value (e.g., based on theexpected propagation losses) or if it meets an established thresholdvalue (e.g., RSSI losses associated with minor barriers).

Referring to FIG. 21 , with further reference to FIGS. 1-17 , a method2100 for determining barrier type information includes the stages shown.The method 2100 is, however, an example and not limiting. The method2100 may be altered. e.g., by having stages added, removed, rearranged,combined, performed concurrently, and/or having single stages split intomultiple stages.

At stage 2102, the method includes estimating a range value based on atime-of-flight measurement. A wireless node such as the UE 200,including one or more processors 210 and a transceiver 215 is a meansfor estimating a range value based on a time-of-flight measurement. Twowireless nodes, such as UEs, APs, IoT devices, etc., may be configuredto exchange RTT messages to estimate the range value. For example, thewireless nodes may be configured to utilize the FTM Protocol (e.g.,802.11mc D4.3 section 10.24.6) to exchange round trip measurement frames(e.g., FTM frames). Other ToF measurement techniques may also be used toestimate the range.

At stage 2104, the method includes determining an expected receivesignal strength indicator value based on the range value. The UE 200,including one or more processors 210 and a transceiver 215, is a meansfor determining the expected RSSI value. The UE 200 may be configured todetermine the expected RSSI value based on known propagation equations,such as equation (2).

At stage 2106, the method includes obtaining a received signal strengthindicator measurement value. The UE 200, including one or moreprocessors 210 and a transceiver 215, is a means for obtaining the RSSImeasurement value. The RSSI value may be based on the RTT messageexchange, or other signals transmitted between wireless nodes.

At stage 2108, the method includes determining a received signalstrength indicator delta value based on the expected received signalstrength indicator value and the received signal strength indicatormeasurement value. The UE 200, including one or more processors 210 anda transceiver 215, is a means for determining the RSSI delta value. TheRSSI delta value may be difference between the expected RSSI valuedetermined at stage 2104 and the RSSI measurement value obtained atstage 2106.

At stage 2110, the method includes determining barrier type informationbased on a comparison of the received signal strength delta value to oneor more threshold values. The UE 200, including one or more processors210 and a memory 211, is a means for determining the barrier typeinformation. In an example, referring to FIG. 9 , one or more thresholdvalues may be associated with different barrier types. The thresholdvalues may be stored in a data structure (e.g., LUT) in a local ornetworked memory and the UE 200 may be configured to compare the RSSIdelta value with the threshold values in the data structure to determinethe barrier type information.

Other examples and implementations are within the scope of thedisclosure and appended claims. For example, due to the nature ofsoftware and computers, functions described above can be implementedusing software executed by a processor, hardware, firmware, hardwiring,or a combination of any of these. Features implementing functions mayalso be physically located at various positions, including beingdistributed such that portions of functions are implemented at differentphysical locations. For example, one or more functions, or one or moreportions thereof, discussed above as occurring in the LMF 120 may beperformed outside of the LMF 120 such as by the TRP 300.

As used herein, the singular forms “a,” “an,” and “the” include theplural forms as well, unless the context clearly indicates otherwise.For example, “a processor” may include one processor or multipleprocessors. The terms “comprises,” “comprising,” “includes,” and/or“including,” as used herein, specify the presence of stated features,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof.

Also, as used herein, “or” as used in a list of items prefaced by “atleast one of” or prefaced by “one or more of” indicates a disjunctivelist such that, for example, a list of “at least one of A. B, or C,” ora list of “one or more of A, B, or C” means A or B or C or AB or AC orBC or ABC (i.e., A and B and C), or combinations with more than onefeature (e.g., AA, AAB, ABBC, etc.).

Substantial variations may be made in accordance with specificrequirements. For example, customized hardware might also be used,and/or particular elements might be implemented in hardware, software(including portable software, such as applets, etc.) executed by aprocessor, or both. Further, connection to other computing devices suchas network input/output devices may be employed.

The systems and devices discussed above are examples. Variousconfigurations may omit, substitute, or add various procedures orcomponents as appropriate. For instance, features described with respectto certain configurations may be combined in various otherconfigurations. Different aspects and elements of the configurations maybe combined in a similar manner. Also, technology evolves and, thus,many of the elements are examples and do not limit the scope of thedisclosure or claims.

A wireless communication system is one in which communications areconveyed wirelessly, i.e., by electromagnetic and/or acoustic wavespropagating through atmospheric space rather than through a wire orother physical connection. A wireless communication network may not haveall communications transmitted wirelessly, but is configured to have atleast some communications transmitted wirelessly. Further, the term“wireless communication device,” or similar term, does not require thatthe functionality of the device is exclusively, or evenly primarily, forcommunication, or that the device be a mobile device, but indicates thatthe device includes wireless communication capability (one-way ortwo-way), e.g., includes at least one radio (each radio being part of atransmitter, receiver, or transceiver) for wireless communication.

Specific details are given in the description to provide a thoroughunderstanding of example configurations (including implementations).However, configurations may be practiced without these specific details.For example, well-known circuits, processes, algorithms, structures, andtechniques have been shown without unnecessary detail in order to avoidobscuring the configurations. This description provides exampleconfigurations, and does not limit the scope, applicability, orconfigurations of the claims. Rather, the preceding description of theconfigurations provides a description for implementing describedtechniques. Various changes may be made in the function and arrangementof elements without departing from the scope of the disclosure.

The terms “processor-readable medium,” “machine-readable medium.” and“computer-readable medium.” as used herein, refer to any medium thatparticipates in providing data that causes a machine to operate in aspecific fashion. Using a computing platform, various processor-readablemedia might be involved in providing instructions/code to processor(s)for execution and/or might be used to store and/or carry suchinstructions/code (e.g., as signals). In many implementations, aprocessor-readable medium is a physical and/or tangible storage medium.Such a medium may take many forms, including but not limited to,non-volatile media and volatile media. Non-volatile media include, forexample, optical and/or magnetic disks. Volatile media include, withoutlimitation, dynamic memory.

A statement that a value exceeds (or is more than or above) a firstthreshold value is equivalent to a statement that the value meets orexceeds a second threshold value that is slightly greater than the firstthreshold value, e.g., the second threshold value being one value higherthan the first threshold value in the resolution of a computing system.A statement that a value is less than (or is within or below) a firstthreshold value is equivalent to a statement that the value is less thanor equal to a second threshold value that is slightly lower than thefirst threshold value, e.g., the second threshold value being one valuelower than the first threshold value in the resolution of a computingsystem.

Implementation examples are described in the following numbered clauses:

Clause 1. A method for detecting a change in state of a physicalenvironment, comprising: determining a first state of the physicalenvironment based on one or more round trip time measurements and one ormore received signal strength measurements associated with a firstplurality of radio frequency signals exchanged with one or more wirelessnodes; determining a second state of the physical environment based onone or more round trip time measurements and one or more received signalstrength measurements associated with a second plurality of radiofrequency signals exchanged with the one or more wireless nodes; andproviding an indication of a state change in the physical environmentbased at least in part on a comparison of the first state and the secondstate.

Clause 2. The method of clause 1 wherein determining the first stateincludes determining that a barrier is present in the first state of thephysical environment based on the one or more round trip timemeasurements and the one or more received signal strength measurementsassociated with the first plurality of radio frequency signals, anddetermining that a barrier is not present in the second state of thephysical environment based on the one or more round trip timemeasurements and the one or more received signal strength measurementsassociated with the second plurality of radio frequency signals.

Clause 3. The method of clause 2 further comprising determining abarrier type associated with the barrier.

Clause 4. The method of clause 3 further comprising providing anindication of the barrier type to one or more controllers.

Clause 5. The method of clause 2 wherein the barrier is a liquid and theindication of the state change is a flooding alarm.

Clause 6. The method of clause 1 wherein the physical environmentincludes a door, and wherein determining the first state includesdetermining that the door is in an open state, and determining thesecond state includes determining that the door is in a closed state.

Clause 7. The method of clause 1 wherein the physical environmentincludes a window, and wherein determining the first state includesdetermining that the window is in an open state, and determining thesecond state includes determining that the window is in a closed state.

Clause 8. The method of clause 1 wherein the physical environmentincludes a plurality of vehicles, wherein determining the first stateincludes determining that a first number of vehicles are present in thephysical environment, and determining the second state includesdetermining that a second number of vehicles are present in the physicalenvironment, and wherein the second number of vehicles is different fromthe first number of vehicles.

Clause 9. The method of clause 1 wherein the physical environmentincludes a plurality of items disposed on one or more shelves, whereindetermining the first state includes determining that a first number ofitems are disposed on the one or more shelves, and determining thesecond state includes determining that a second number of items aredisposed on the one or more shelves, and wherein the second number ofitems is different from the first number of items.

Clause 10. The method of clause 1 wherein the first plurality of radiofrequency signals and the second plurality of radio frequency signalsutilize at least one radio access technology selected from a groupconsisting of WiFi, Bluetooth, ultrawideband (UWB), and fifth generationnew radio.

Clause 11. The method of clause 1 further comprising obtaining radiofrequency sensing information for the physical environment, whereindetermining the first state of the physical environment or determiningthe second state of the physical environment are based at least in parton the radio frequency sensing information.

Clause 12. The method of clause 1 further comprising obtaining angle ofarrival measurements based on the first plurality of radio frequencysignals or the second plurality of radio frequency signals, whereindetermining the first state of the physical environment or determiningthe second state of the physical environment are based at least in parton the angle of arrival measurements.

Clause 13. The method of clause 1 wherein the one or more wireless nodesincludes a user equipment.

Clause 14. The method of clause 1 wherein the one or more wireless nodesincludes an access point.

Clause 15. An apparatus, comprising: a memory; at least one transceiver;at least one processor communicatively coupled to the memory and the atleast one transceiver, and configured to: determine a first state of aphysical environment based on one or more round trip time measurementsand one or more received signal strength measurements associated with afirst plurality of radio frequency signals exchanged with one or morewireless nodes; determine a second state of the physical environmentbased on one or more round trip time measurements and one or morereceived signal strength measurements associated with a second pluralityof radio frequency signals exchanged with the one or more wirelessnodes; and provide an indication of a state change in the physicalenvironment based at least in part on a comparison of the first stateand the second state.

Clause 16. The apparatus of clause 15 wherein the at least one processoris further configured to determine that a barrier is present in thefirst state of the physical environment based on the one or more roundtrip time measurements and the one or more received signal strengthmeasurements associated with the first plurality of radio frequencysignals, and determine that a barrier is not present in the second stateof the physical environment based on the one or more round trip timemeasurements and the one or more received signal strength measurementsassociated with the second plurality of radio frequency signals.

Clause 17. The apparatus of clause 16 wherein the at least one processoris further configured to determine a barrier type associated with thebarrier.

Clause 18. The apparatus of clause 17 wherein the at least one processoris further configured to provide an indication of the barrier type toone or more controllers.

Clause 19. The apparatus of clause 17 wherein the barrier is a liquidand the indication of the state change is a flooding alarm.

Clause 20. The apparatus of clause 15 wherein the physical environmentincludes a door, and the at least one processor is further configured todetermine that the door is in an open state, or determine that the dooris in a closed state.

Clause 21. The apparatus of clause 15 wherein the physical environmentincludes a window, and the at least one processor is further configuredto determine that the window is in an open state, or determine that thewindow is in a closed state.

Clause 22. The apparatus of clause 15 wherein the physical environmentincludes a plurality of vehicles, and the at least one processor isfurther configured to determine that a first number of vehicles arepresent in the physical environment in the first state, and determinethat a second number of vehicles are present in the physical environmentin the second state, wherein the second number of vehicles is differentfrom the first number of vehicles.

Clause 23. The apparatus of clause 15 wherein the physical environmentincludes a plurality of items disposed on one or more shelves, and theat least one processor is further configured to determine that a firstnumber of items are disposed on the one or more shelves in the firststate, and determine that a second number of items are disposed on theone or more shelves in the second state, and wherein the second numberof items is different from the first number of items.

Clause 24. The apparatus of clause 15 wherein the first plurality ofradio frequency signals and the second plurality of radio frequencysignals utilize at least one radio access technology selected from agroup consisting of WiFi. Bluetooth, ultrawideband (UWB), and fifthgeneration new radio.

Clause 25. The apparatus of clause 15 wherein the at least one processoris further configured to obtain radio frequency sensing information forthe physical environment, and determine the first state of the physicalenvironment or determine the second state of the physical environmentbased at least in part on the radio frequency sensing information.

Clause 26. The apparatus of clause 15 wherein the at least one processoris further configured to obtain angle of arrival measurements based onthe first plurality of radio frequency signals or the second pluralityof radio frequency signals, and determine the first state of thephysical environment or determine the second state of the physicalenvironment based at least in part on the angle of arrival measurements.

Clause 27. The apparatus of clause 15 wherein the one or more wirelessnodes includes a user equipment.

Clause 28. The apparatus of clause 15 wherein the one or more wirelessnodes includes an access point.

Clause 29. An apparatus for detecting a change in state of a physicalenvironment, comprising: means for determining a first state of thephysical environment based on one or more round trip time measurementsand one or more received signal strength measurements associated with afirst plurality of radio frequency signals exchanged with one or morewireless nodes; means for determining a second state of the physicalenvironment based on one or more round trip time measurements and one ormore received signal strength measurements associated with a secondplurality of radio frequency signals exchanged with the one or morewireless nodes; and means for providing an indication of a state changein the physical environment based at least in part on a comparison ofthe first state and the second state.

Clause 30. A non-transitory processor-readable storage medium comprisingprocessor-readable instructions configured to cause one or moreprocessors to detect a change in state of a physical environment,comprising code for: determining a first state of the physicalenvironment based on one or more round trip time measurements and one ormore received signal strength measurements associated with a firstplurality of radio frequency signals exchanged with one or more wirelessnodes; determining a second state of the physical environment based onone or more round trip time measurements and one or more received signalstrength measurements associated with a second plurality of radiofrequency signals exchanged with the one or more wireless nodes; andproviding an indication of a state change in the physical environmentbased at least in part on a comparison of the first state and the secondstate.

1. A method for detecting a change in state of a physical environment,comprising: determining a first state of the physical environment basedon one or more round trip time measurements and one or more receivedsignal strength measurements associated with a first plurality of radiofrequency signals exchanged with one or more wireless nodes; determininga second state of the physical environment based on one or more roundtrip time measurements and one or more received signal strengthmeasurements associated with a second plurality of radio frequencysignals exchanged with the one or more wireless nodes; and providing anindication of a state change in the physical environment based at leastin part on a comparison of the first state and the second state.
 2. Themethod of claim 1 wherein determining the first state includesdetermining that a barrier is present in the first state of the physicalenvironment based on the one or more round trip time measurements andthe one or more received signal strength measurements associated withthe first plurality of radio frequency signals, and determining that abarrier is not present in the second state of the physical environmentbased on the one or more round trip time measurements and the one ormore received signal strength measurements associated with the secondplurality of radio frequency signals.
 3. The method of claim 2 furthercomprising determining a barrier type associated with the barrier. 4.The method of claim 3 further comprising providing an indication of thebarrier type to one or more controllers.
 5. The method of claim 2wherein the barrier is a liquid and the indication of the state changeis a flooding alarm.
 6. The method of claim 1 wherein the physicalenvironment includes a door, and wherein determining the first stateincludes determining that the door is in an open state, and determiningthe second state includes determining that the door is in a closedstate.
 7. The method of claim 1 wherein the physical environmentincludes a window, and wherein determining the first state includesdetermining that the window is in an open state, and determining thesecond state includes determining that the window is in a closed state.8. The method of claim 1 wherein the physical environment includes aplurality of vehicles, wherein determining the first state includesdetermining that a first number of vehicles are present in the physicalenvironment, and determining the second state includes determining thata second number of vehicles are present in the physical environment, andwherein the second number of vehicles is different from the first numberof vehicles.
 9. The method of claim 1 wherein the physical environmentincludes a plurality of items disposed on one or more shelves, whereindetermining the first state includes determining that a first number ofitems are disposed on the one or more shelves, and determining thesecond state includes determining that a second number of items aredisposed on the one or more shelves, and wherein the second number ofitems is different from the first number of items.
 10. The method ofclaim 1 wherein the first plurality of radio frequency signals and thesecond plurality of radio frequency signals utilize at least one radioaccess technology selected from a group consisting of WiFi, Bluetooth,ultrawideband (UWB), and fifth generation new radio.
 11. The method ofclaim 1 further comprising obtaining radio frequency sensing informationfor the physical environment, wherein determining the first state of thephysical environment or determining the second state of the physicalenvironment are based at least in part on the radio frequency sensinginformation.
 12. The method of claim 1 further comprising obtainingangle of arrival measurements based on the first plurality of radiofrequency signals or the second plurality of radio frequency signals,wherein determining the first state of the physical environment ordetermining the second state of the physical environment are based atleast in part on the angle of arrival measurements.
 13. The method ofclaim 1 wherein the one or more wireless nodes includes a userequipment.
 14. The method of claim 1 wherein the one or more wirelessnodes includes an access point.
 15. An apparatus, comprising: a memory;at least one transceiver; at least one processor communicatively coupledto the memory and the at least one transceiver, and configured to:determine a first state of a physical environment based on one or moreround trip time measurements and one or more received signal strengthmeasurements associated with a first plurality of radio frequencysignals exchanged with one or more wireless nodes; determine a secondstate of the physical environment based on one or more round trip timemeasurements and one or more received signal strength measurementsassociated with a second plurality of radio frequency signals exchangedwith the one or more wireless nodes; and provide an indication of astate change in the physical environment based at least in part on acomparison of the first state and the second state.
 16. The apparatus ofclaim 15 wherein the at least one processor is further configured todetermine that a barrier is present in the first state of the physicalenvironment based on the one or more round trip time measurements andthe one or more received signal strength measurements associated withthe first plurality of radio frequency signals, and determine that abarrier is not present in the second state of the physical environmentbased on the one or more round trip time measurements and the one ormore received signal strength measurements associated with the secondplurality of radio frequency signals.
 17. The apparatus of claim 16wherein the at least one processor is further configured to determine abarrier type associated with the barrier.
 18. The apparatus of claim 17wherein the at least one processor is further configured to provide anindication of the barrier type to one or more controllers.
 19. Theapparatus of claim 17 wherein the barrier is a liquid and the indicationof the state change is a flooding alarm.
 20. The apparatus of claim 15wherein the physical environment includes a door, and the at least oneprocessor is further configured to determine that the door is in an openstate, or determine that the door is in a closed state.
 21. Theapparatus of claim 15 wherein the physical environment includes awindow, and the at least one processor is further configured todetermine that the window is in an open state, or determine that thewindow is in a closed state.
 22. The apparatus of claim 15 wherein thephysical environment includes a plurality of vehicles, and the at leastone processor is further configured to determine that a first number ofvehicles are present in the physical environment in the first state, anddetermine that a second number of vehicles are present in the physicalenvironment in the second state, wherein the second number of vehiclesis different from the first number of vehicles.
 23. The apparatus ofclaim 15 wherein the physical environment includes a plurality of itemsdisposed on one or more shelves, and the at least one processor isfurther configured to determine that a first number of items aredisposed on the one or more shelves in the first state, and determinethat a second number of items are disposed on the one or more shelves inthe second state, and wherein the second number of items is differentfrom the first number of items.
 24. The apparatus of claim 15 whereinthe first plurality of radio frequency signals and the second pluralityof radio frequency signals utilize at least one radio access technologyselected from a group consisting of WiFi, Bluetooth, ultrawideband(UWB), and fifth generation new radio.
 25. The apparatus of claim 15wherein the at least one processor is further configured to obtain radiofrequency sensing information for the physical environment, anddetermine the first state of the physical environment or determine thesecond state of the physical environment based at least in part on theradio frequency sensing information.
 26. The apparatus of claim 15wherein the at least one processor is further configured to obtain angleof arrival measurements based on the first plurality of radio frequencysignals or the second plurality of radio frequency signals, anddetermine the first state of the physical environment or determine thesecond state of the physical environment based at least in part on theangle of arrival measurements.
 27. The apparatus of claim 15 wherein theone or more wireless nodes includes a user equipment.
 28. The apparatusof claim 15 wherein the one or more wireless nodes includes an accesspoint.
 29. An apparatus for detecting a change in state of a physicalenvironment, comprising: means for determining a first state of thephysical environment based on one or more round trip time measurementsand one or more received signal strength measurements associated with afirst plurality of radio frequency signals exchanged with one or morewireless nodes; means for determining a second state of the physicalenvironment based on one or more round trip time measurements and one ormore received signal strength measurements associated with a secondplurality of radio frequency signals exchanged with the one or morewireless nodes; and means for providing an indication of a state changein the physical environment based at least in part on a comparison ofthe first state and the second state.
 30. A non-transitoryprocessor-readable storage medium comprising processor-readableinstructions configured to cause one or more processors to detect achange in state of a physical environment, comprising code for:determining a first state of the physical environment based on one ormore round trip time measurements and one or more received signalstrength measurements associated with a first plurality of radiofrequency signals exchanged with one or more wireless nodes; determininga second state of the physical environment based on one or more roundtrip time measurements and one or more received signal strengthmeasurements associated with a second plurality of radio frequencysignals exchanged with the one or more wireless nodes; and providing anindication of a state change in the physical environment based at leastin part on a comparison of the first state and the second state.